/**
* @license
* lodash 3.2.0 (Custom Build)
* Build: `lodash modern -d -o ./index.js`
* Copyright 2012-2015 The Dojo Foundation
* Based on Underscore.js 1.7.0
* Copyright 2009-2015 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license
*/
;(function() {
/** Used as a safe reference for `undefined` in pre-ES5 environments. */
var undefined;
/** Used as the semantic version number. */
var VERSION = '3.2.0';
/** Used to compose bitmasks for wrapper metadata. */
var BIND_FLAG = 1,
BIND_KEY_FLAG = 2,
CURRY_BOUND_FLAG = 4,
CURRY_FLAG = 8,
CURRY_RIGHT_FLAG = 16,
PARTIAL_FLAG = 32,
PARTIAL_RIGHT_FLAG = 64,
REARG_FLAG = 128,
ARY_FLAG = 256;
/** Used as default options for `_.trunc`. */
var DEFAULT_TRUNC_LENGTH = 30,
DEFAULT_TRUNC_OMISSION = '...';
/** Used to detect when a function becomes hot. */
var HOT_COUNT = 150,
HOT_SPAN = 16;
/** Used to indicate the type of lazy iteratees. */
var LAZY_FILTER_FLAG = 0,
LAZY_MAP_FLAG = 1,
LAZY_WHILE_FLAG = 2;
/** Used as the `TypeError` message for "Functions" methods. */
var FUNC_ERROR_TEXT = 'Expected a function';
/** Used as the internal argument placeholder. */
var PLACEHOLDER = '__lodash_placeholder__';
/** `Object#toString` result references. */
var argsTag = '[object Arguments]',
arrayTag = '[object Array]',
boolTag = '[object Boolean]',
dateTag = '[object Date]',
errorTag = '[object Error]',
funcTag = '[object Function]',
mapTag = '[object Map]',
numberTag = '[object Number]',
objectTag = '[object Object]',
regexpTag = '[object RegExp]',
setTag = '[object Set]',
stringTag = '[object String]',
weakMapTag = '[object WeakMap]';
var arrayBufferTag = '[object ArrayBuffer]',
float32Tag = '[object Float32Array]',
float64Tag = '[object Float64Array]',
int8Tag = '[object Int8Array]',
int16Tag = '[object Int16Array]',
int32Tag = '[object Int32Array]',
uint8Tag = '[object Uint8Array]',
uint8ClampedTag = '[object Uint8ClampedArray]',
uint16Tag = '[object Uint16Array]',
uint32Tag = '[object Uint32Array]';
/** Used to match empty string literals in compiled template source. */
var reEmptyStringLeading = /\b__p \+= '';/g,
reEmptyStringMiddle = /\b(__p \+=) '' \+/g,
reEmptyStringTrailing = /(__e\(.*?\)|\b__t\)) \+\n'';/g;
/** Used to match HTML entities and HTML characters. */
var reEscapedHtml = /&(?:amp|lt|gt|quot|#39|#96);/g,
reUnescapedHtml = /[&<>"'`]/g,
reHasEscapedHtml = RegExp(reEscapedHtml.source),
reHasUnescapedHtml = RegExp(reUnescapedHtml.source);
/** Used to match template delimiters. */
var reEscape = /<%-([\s\S]+?)%>/g,
reEvaluate = /<%([\s\S]+?)%>/g,
reInterpolate = /<%=([\s\S]+?)%>/g;
/**
* Used to match ES template delimiters.
* See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-template-literal-lexical-components)
* for more details.
*/
var reEsTemplate = /\$\{([^\\}]*(?:\\.[^\\}]*)*)\}/g;
/** Used to match `RegExp` flags from their coerced string values. */
var reFlags = /\w*$/;
/** Used to detect named functions. */
var reFuncName = /^\s*function[ \n\r\t]+\w/;
/** Used to detect hexadecimal string values. */
var reHexPrefix = /^0[xX]/;
/** Used to detect host constructors (Safari > 5). */
var reHostCtor = /^\[object .+?Constructor\]$/;
/** Used to match latin-1 supplementary letters (excluding mathematical operators). */
var reLatin1 = /[\xc0-\xd6\xd8-\xde\xdf-\xf6\xf8-\xff]/g;
/** Used to ensure capturing order of template delimiters. */
var reNoMatch = /($^)/;
/**
* Used to match `RegExp` special characters.
* See this [article on `RegExp` characters](http://www.regular-expressions.info/characters.html#special)
* for more details.
*/
var reRegExpChars = /[.*+?^${}()|[\]\/\\]/g,
reHasRegExpChars = RegExp(reRegExpChars.source);
/** Used to detect functions containing a `this` reference. */
var reThis = /\bthis\b/;
/** Used to match unescaped characters in compiled string literals. */
var reUnescapedString = /['\n\r\u2028\u2029\\]/g;
/** Used to match words to create compound words. */
var reWords = (function() {
var upper = '[A-Z\\xc0-\\xd6\\xd8-\\xde]',
lower = '[a-z\\xdf-\\xf6\\xf8-\\xff]+';
return RegExp(upper + '{2,}(?=' + upper + lower + ')|' + upper + '?' + lower + '|' + upper + '+|[0-9]+', 'g');
}());
/** Used to detect and test for whitespace. */
var whitespace = (
// Basic whitespace characters.
' \t\x0b\f\xa0\ufeff' +
// Line terminators.
'\n\r\u2028\u2029' +
// Unicode category "Zs" space separators.
'\u1680\u180e\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u202f\u205f\u3000'
);
/** Used to assign default `context` object properties. */
var contextProps = [
'Array', 'ArrayBuffer', 'Date', 'Error', 'Float32Array', 'Float64Array',
'Function', 'Int8Array', 'Int16Array', 'Int32Array', 'Math', 'Number',
'Object', 'RegExp', 'Set', 'String', '_', 'clearTimeout', 'document',
'isFinite', 'parseInt', 'setTimeout', 'TypeError', 'Uint8Array',
'Uint8ClampedArray', 'Uint16Array', 'Uint32Array', 'WeakMap',
'window', 'WinRTError'
];
/** Used to make template sourceURLs easier to identify. */
var templateCounter = -1;
/** Used to identify `toStringTag` values of typed arrays. */
var typedArrayTags = {};
typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =
typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] =
typedArrayTags[uint32Tag] = true;
typedArrayTags[argsTag] = typedArrayTags[arrayTag] =
typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] =
typedArrayTags[dateTag] = typedArrayTags[errorTag] =
typedArrayTags[funcTag] = typedArrayTags[mapTag] =
typedArrayTags[numberTag] = typedArrayTags[objectTag] =
typedArrayTags[regexpTag] = typedArrayTags[setTag] =
typedArrayTags[stringTag] = typedArrayTags[weakMapTag] = false;
/** Used to identify `toStringTag` values supported by `_.clone`. */
var cloneableTags = {};
cloneableTags[argsTag] = cloneableTags[arrayTag] =
cloneableTags[arrayBufferTag] = cloneableTags[boolTag] =
cloneableTags[dateTag] = cloneableTags[float32Tag] =
cloneableTags[float64Tag] = cloneableTags[int8Tag] =
cloneableTags[int16Tag] = cloneableTags[int32Tag] =
cloneableTags[numberTag] = cloneableTags[objectTag] =
cloneableTags[regexpTag] = cloneableTags[stringTag] =
cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] =
cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true;
cloneableTags[errorTag] = cloneableTags[funcTag] =
cloneableTags[mapTag] = cloneableTags[setTag] =
cloneableTags[weakMapTag] = false;
/** Used as an internal `_.debounce` options object by `_.throttle`. */
var debounceOptions = {
'leading': false,
'maxWait': 0,
'trailing': false
};
/** Used to map latin-1 supplementary letters to basic latin letters. */
var deburredLetters = {
'\xc0': 'A', '\xc1': 'A', '\xc2': 'A', '\xc3': 'A', '\xc4': 'A', '\xc5': 'A',
'\xe0': 'a', '\xe1': 'a', '\xe2': 'a', '\xe3': 'a', '\xe4': 'a', '\xe5': 'a',
'\xc7': 'C', '\xe7': 'c',
'\xd0': 'D', '\xf0': 'd',
'\xc8': 'E', '\xc9': 'E', '\xca': 'E', '\xcb': 'E',
'\xe8': 'e', '\xe9': 'e', '\xea': 'e', '\xeb': 'e',
'\xcC': 'I', '\xcd': 'I', '\xce': 'I', '\xcf': 'I',
'\xeC': 'i', '\xed': 'i', '\xee': 'i', '\xef': 'i',
'\xd1': 'N', '\xf1': 'n',
'\xd2': 'O', '\xd3': 'O', '\xd4': 'O', '\xd5': 'O', '\xd6': 'O', '\xd8': 'O',
'\xf2': 'o', '\xf3': 'o', '\xf4': 'o', '\xf5': 'o', '\xf6': 'o', '\xf8': 'o',
'\xd9': 'U', '\xda': 'U', '\xdb': 'U', '\xdc': 'U',
'\xf9': 'u', '\xfa': 'u', '\xfb': 'u', '\xfc': 'u',
'\xdd': 'Y', '\xfd': 'y', '\xff': 'y',
'\xc6': 'Ae', '\xe6': 'ae',
'\xde': 'Th', '\xfe': 'th',
'\xdf': 'ss'
};
/** Used to map characters to HTML entities. */
var htmlEscapes = {
'&': '&',
'<': '<',
'>': '>',
'"': '"',
"'": ''',
'`': '`'
};
/** Used to map HTML entities to characters. */
var htmlUnescapes = {
'&': '&',
'<': '<',
'>': '>',
'"': '"',
''': "'",
'`': '`'
};
/** Used to determine if values are of the language type `Object`. */
var objectTypes = {
'function': true,
'object': true
};
/** Used to escape characters for inclusion in compiled string literals. */
var stringEscapes = {
'\\': '\\',
"'": "'",
'\n': 'n',
'\r': 'r',
'\u2028': 'u2028',
'\u2029': 'u2029'
};
/**
* Used as a reference to the global object.
*
* The `this` value is used if it is the global object to avoid Greasemonkey's
* restricted `window` object, otherwise the `window` object is used.
*/
var root = (objectTypes[typeof window] && window !== (this && this.window)) ? window : this;
/** Detect free variable `exports`. */
var freeExports = objectTypes[typeof exports] && exports && !exports.nodeType && exports;
/** Detect free variable `module`. */
var freeModule = objectTypes[typeof module] && module && !module.nodeType && module;
/** Detect free variable `global` from Node.js or Browserified code and use it as `root`. */
var freeGlobal = freeExports && freeModule && typeof global == 'object' && global;
if (freeGlobal && (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal || freeGlobal.self === freeGlobal)) {
root = freeGlobal;
}
/** Detect the popular CommonJS extension `module.exports`. */
var moduleExports = freeModule && freeModule.exports === freeExports && freeExports;
/*--------------------------------------------------------------------------*/
/**
* The base implementation of `compareAscending` which compares values and
* sorts them in ascending order without guaranteeing a stable sort.
*
* @private
* @param {*} value The value to compare to `other`.
* @param {*} other The value to compare to `value`.
* @returns {number} Returns the sort order indicator for `value`.
*/
function baseCompareAscending(value, other) {
if (value !== other) {
var valIsReflexive = value === value,
othIsReflexive = other === other;
if (value > other || !valIsReflexive || (typeof value == 'undefined' && othIsReflexive)) {
return 1;
}
if (value < other || !othIsReflexive || (typeof other == 'undefined' && valIsReflexive)) {
return -1;
}
}
return 0;
}
/**
* The base implementation of `_.indexOf` without support for binary searches.
*
* @private
* @param {Array} array The array to search.
* @param {*} value The value to search for.
* @param {number} [fromIndex=0] The index to search from.
* @returns {number} Returns the index of the matched value, else `-1`.
*/
function baseIndexOf(array, value, fromIndex) {
if (value !== value) {
return indexOfNaN(array, fromIndex);
}
var index = (fromIndex || 0) - 1,
length = array.length;
while (++index < length) {
if (array[index] === value) {
return index;
}
}
return -1;
}
/**
* The base implementation of `_.sortBy` and `_.sortByAll` which uses `comparer`
* to define the sort order of `array` and replaces criteria objects with their
* corresponding values.
*
* @private
* @param {Array} array The array to sort.
* @param {Function} comparer The function to define sort order.
* @returns {Array} Returns `array`.
*/
function baseSortBy(array, comparer) {
var length = array.length;
array.sort(comparer);
while (length--) {
array[length] = array[length].value;
}
return array;
}
/**
* Converts `value` to a string if it is not one. An empty string is returned
* for `null` or `undefined` values.
*
* @private
* @param {*} value The value to process.
* @returns {string} Returns the string.
*/
function baseToString(value) {
if (typeof value == 'string') {
return value;
}
return value == null ? '' : (value + '');
}
/**
* Used by `_.max` and `_.min` as the default callback for string values.
*
* @private
* @param {string} string The string to inspect.
* @returns {number} Returns the code unit of the first character of the string.
*/
function charAtCallback(string) {
return string.charCodeAt(0);
}
/**
* Used by `_.trim` and `_.trimLeft` to get the index of the first character
* of `string` that is not found in `chars`.
*
* @private
* @param {string} string The string to inspect.
* @param {string} chars The characters to find.
* @returns {number} Returns the index of the first character not found in `chars`.
*/
function charsLeftIndex(string, chars) {
var index = -1,
length = string.length;
while (++index < length && chars.indexOf(string.charAt(index)) > -1) {}
return index;
}
/**
* Used by `_.trim` and `_.trimRight` to get the index of the last character
* of `string` that is not found in `chars`.
*
* @private
* @param {string} string The string to inspect.
* @param {string} chars The characters to find.
* @returns {number} Returns the index of the last character not found in `chars`.
*/
function charsRightIndex(string, chars) {
var index = string.length;
while (index-- && chars.indexOf(string.charAt(index)) > -1) {}
return index;
}
/**
* Used by `_.sortBy` to compare transformed elements of a collection and stable
* sort them in ascending order.
*
* @private
* @param {Object} object The object to compare to `other`.
* @param {Object} other The object to compare to `object`.
* @returns {number} Returns the sort order indicator for `object`.
*/
function compareAscending(object, other) {
return baseCompareAscending(object.criteria, other.criteria) || (object.index - other.index);
}
/**
* Used by `_.sortByAll` to compare multiple properties of each element
* in a collection and stable sort them in ascending order.
*
* @private
* @param {Object} object The object to compare to `other`.
* @param {Object} other The object to compare to `object`.
* @returns {number} Returns the sort order indicator for `object`.
*/
function compareMultipleAscending(object, other) {
var index = -1,
objCriteria = object.criteria,
othCriteria = other.criteria,
length = objCriteria.length;
while (++index < length) {
var result = baseCompareAscending(objCriteria[index], othCriteria[index]);
if (result) {
return result;
}
}
// Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications
// that causes it, under certain circumstances, to provide the same value for
// `object` and `other`. See https://github.com/jashkenas/underscore/pull/1247
// for more details.
//
// This also ensures a stable sort in V8 and other engines.
// See https://code.google.com/p/v8/issues/detail?id=90 for more details.
return object.index - other.index;
}
/**
* Used by `_.deburr` to convert latin-1 supplementary letters to basic latin letters.
*
* @private
* @param {string} letter The matched letter to deburr.
* @returns {string} Returns the deburred letter.
*/
function deburrLetter(letter) {
return deburredLetters[letter];
}
/**
* Used by `_.escape` to convert characters to HTML entities.
*
* @private
* @param {string} chr The matched character to escape.
* @returns {string} Returns the escaped character.
*/
function escapeHtmlChar(chr) {
return htmlEscapes[chr];
}
/**
* Used by `_.template` to escape characters for inclusion in compiled
* string literals.
*
* @private
* @param {string} chr The matched character to escape.
* @returns {string} Returns the escaped character.
*/
function escapeStringChar(chr) {
return '\\' + stringEscapes[chr];
}
/**
* Gets the index at which the first occurrence of `NaN` is found in `array`.
* If `fromRight` is provided elements of `array` are iterated from right to left.
*
* @private
* @param {Array} array The array to search.
* @param {number} [fromIndex] The index to search from.
* @param {boolean} [fromRight] Specify iterating from right to left.
* @returns {number} Returns the index of the matched `NaN`, else `-1`.
*/
function indexOfNaN(array, fromIndex, fromRight) {
var length = array.length,
index = fromRight ? (fromIndex || length) : ((fromIndex || 0) - 1);
while ((fromRight ? index-- : ++index < length)) {
var other = array[index];
if (other !== other) {
return index;
}
}
return -1;
}
/**
* Checks if `value` is object-like.
*
* @private
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is object-like, else `false`.
*/
function isObjectLike(value) {
return (value && typeof value == 'object') || false;
}
/**
* Used by `trimmedLeftIndex` and `trimmedRightIndex` to determine if a
* character code is whitespace.
*
* @private
* @param {number} charCode The character code to inspect.
* @returns {boolean} Returns `true` if `charCode` is whitespace, else `false`.
*/
function isSpace(charCode) {
return ((charCode <= 160 && (charCode >= 9 && charCode <= 13) || charCode == 32 || charCode == 160) || charCode == 5760 || charCode == 6158 ||
(charCode >= 8192 && (charCode <= 8202 || charCode == 8232 || charCode == 8233 || charCode == 8239 || charCode == 8287 || charCode == 12288 || charCode == 65279)));
}
/**
* Replaces all `placeholder` elements in `array` with an internal placeholder
* and returns an array of their indexes.
*
* @private
* @param {Array} array The array to modify.
* @param {*} placeholder The placeholder to replace.
* @returns {Array} Returns the new array of placeholder indexes.
*/
function replaceHolders(array, placeholder) {
var index = -1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
if (array[index] === placeholder) {
array[index] = PLACEHOLDER;
result[++resIndex] = index;
}
}
return result;
}
/**
* An implementation of `_.uniq` optimized for sorted arrays without support
* for callback shorthands and `this` binding.
*
* @private
* @param {Array} array The array to inspect.
* @param {Function} [iteratee] The function invoked per iteration.
* @returns {Array} Returns the new duplicate-value-free array.
*/
function sortedUniq(array, iteratee) {
var seen,
index = -1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index],
computed = iteratee ? iteratee(value, index, array) : value;
if (!index || seen !== computed) {
seen = computed;
result[++resIndex] = value;
}
}
return result;
}
/**
* Used by `_.trim` and `_.trimLeft` to get the index of the first non-whitespace
* character of `string`.
*
* @private
* @param {string} string The string to inspect.
* @returns {number} Returns the index of the first non-whitespace character.
*/
function trimmedLeftIndex(string) {
var index = -1,
length = string.length;
while (++index < length && isSpace(string.charCodeAt(index))) {}
return index;
}
/**
* Used by `_.trim` and `_.trimRight` to get the index of the last non-whitespace
* character of `string`.
*
* @private
* @param {string} string The string to inspect.
* @returns {number} Returns the index of the last non-whitespace character.
*/
function trimmedRightIndex(string) {
var index = string.length;
while (index-- && isSpace(string.charCodeAt(index))) {}
return index;
}
/**
* Used by `_.unescape` to convert HTML entities to characters.
*
* @private
* @param {string} chr The matched character to unescape.
* @returns {string} Returns the unescaped character.
*/
function unescapeHtmlChar(chr) {
return htmlUnescapes[chr];
}
/*--------------------------------------------------------------------------*/
/**
* Create a new pristine `lodash` function using the given `context` object.
*
* @static
* @memberOf _
* @category Utility
* @param {Object} [context=root] The context object.
* @returns {Function} Returns a new `lodash` function.
* @example
*
* _.mixin({ 'add': function(a, b) { return a + b; } });
*
* var lodash = _.runInContext();
* lodash.mixin({ 'sub': function(a, b) { return a - b; } });
*
* _.isFunction(_.add);
* // => true
* _.isFunction(_.sub);
* // => false
*
* lodash.isFunction(lodash.add);
* // => false
* lodash.isFunction(lodash.sub);
* // => true
*
* // using `context` to mock `Date#getTime` use in `_.now`
* var mock = _.runInContext({
* 'Date': function() {
* return { 'getTime': getTimeMock };
* }
* });
*
* // or creating a suped-up `defer` in Node.js
* var defer = _.runInContext({ 'setTimeout': setImmediate }).defer;
*/
function runInContext(context) {
// Avoid issues with some ES3 environments that attempt to use values, named
// after built-in constructors like `Object`, for the creation of literals.
// ES5 clears this up by stating that literals must use built-in constructors.
// See https://es5.github.io/#x11.1.5 for more details.
context = context ? _.defaults(root.Object(), context, _.pick(root, contextProps)) : root;
/** Native constructor references. */
var Array = context.Array,
Date = context.Date,
Error = context.Error,
Function = context.Function,
Math = context.Math,
Number = context.Number,
Object = context.Object,
RegExp = context.RegExp,
String = context.String,
TypeError = context.TypeError;
/** Used for native method references. */
var arrayProto = Array.prototype,
objectProto = Object.prototype;
/** Used to detect DOM support. */
var document = (document = context.window) && document.document;
/** Used to resolve the decompiled source of functions. */
var fnToString = Function.prototype.toString;
/** Used to the length of n-tuples for `_.unzip`. */
var getLength = baseProperty('length');
/** Used to check objects for own properties. */
var hasOwnProperty = objectProto.hasOwnProperty;
/** Used to generate unique IDs. */
var idCounter = 0;
/**
* Used to resolve the `toStringTag` of values.
* See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.prototype.tostring)
* for more details.
*/
var objToString = objectProto.toString;
/** Used to restore the original `_` reference in `_.noConflict`. */
var oldDash = context._;
/** Used to detect if a method is native. */
var reNative = RegExp('^' +
escapeRegExp(objToString)
.replace(/toString|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
);
/** Native method references. */
var ArrayBuffer = isNative(ArrayBuffer = context.ArrayBuffer) && ArrayBuffer,
bufferSlice = isNative(bufferSlice = ArrayBuffer && new ArrayBuffer(0).slice) && bufferSlice,
ceil = Math.ceil,
clearTimeout = context.clearTimeout,
floor = Math.floor,
getPrototypeOf = isNative(getPrototypeOf = Object.getPrototypeOf) && getPrototypeOf,
push = arrayProto.push,
propertyIsEnumerable = objectProto.propertyIsEnumerable,
Set = isNative(Set = context.Set) && Set,
setTimeout = context.setTimeout,
splice = arrayProto.splice,
Uint8Array = isNative(Uint8Array = context.Uint8Array) && Uint8Array,
WeakMap = isNative(WeakMap = context.WeakMap) && WeakMap;
/** Used to clone array buffers. */
var Float64Array = (function() {
// Safari 5 errors when using an array buffer to initialize a typed array
// where the array buffer's `byteLength` is not a multiple of the typed
// array's `BYTES_PER_ELEMENT`.
try {
var func = isNative(func = context.Float64Array) && func,
result = new func(new ArrayBuffer(10), 0, 1) && func;
} catch(e) {}
return result;
}());
/* Native method references for those with the same name as other `lodash` methods. */
var nativeIsArray = isNative(nativeIsArray = Array.isArray) && nativeIsArray,
nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate,
nativeIsFinite = context.isFinite,
nativeKeys = isNative(nativeKeys = Object.keys) && nativeKeys,
nativeMax = Math.max,
nativeMin = Math.min,
nativeNow = isNative(nativeNow = Date.now) && nativeNow,
nativeNumIsFinite = isNative(nativeNumIsFinite = Number.isFinite) && nativeNumIsFinite,
nativeParseInt = context.parseInt,
nativeRandom = Math.random;
/** Used as references for `-Infinity` and `Infinity`. */
var NEGATIVE_INFINITY = Number.NEGATIVE_INFINITY,
POSITIVE_INFINITY = Number.POSITIVE_INFINITY;
/** Used as references for the maximum length and index of an array. */
var MAX_ARRAY_LENGTH = Math.pow(2, 32) - 1,
MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1,
HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;
/** Used as the size, in bytes, of each `Float64Array` element. */
var FLOAT64_BYTES_PER_ELEMENT = Float64Array ? Float64Array.BYTES_PER_ELEMENT : 0;
/**
* Used as the maximum length of an array-like value.
* See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.max_safe_integer)
* for more details.
*/
var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;
/** Used to store function metadata. */
var metaMap = WeakMap && new WeakMap;
/*------------------------------------------------------------------------*/
/**
* Creates a `lodash` object which wraps `value` to enable implicit chaining.
* Methods that operate on and return arrays, collections, and functions can
* be chained together. Methods that return a boolean or single value will
* automatically end the chain returning the unwrapped value. Explicit chaining
* may be enabled using `_.chain`. The execution of chained methods is lazy,
* that is, execution is deferred until `_#value` is implicitly or explicitly
* called.
*
* Lazy evaluation allows several methods to support shortcut fusion. Shortcut
* fusion is an optimization that merges iteratees to avoid creating intermediate
* arrays and reduce the number of iteratee executions.
*
* Chaining is supported in custom builds as long as the `_#value` method is
* directly or indirectly included in the build.
*
* In addition to lodash methods, wrappers also have the following `Array` methods:
* `concat`, `join`, `pop`, `push`, `reverse`, `shift`, `slice`, `sort`, `splice`,
* and `unshift`
*
* The wrapper methods that support shortcut fusion are:
* `compact`, `drop`, `dropRight`, `dropRightWhile`, `dropWhile`, `filter`,
* `first`, `initial`, `last`, `map`, `pluck`, `reject`, `rest`, `reverse`,
* `slice`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, `toArray`,
* and `where`
*
* The chainable wrapper methods are:
* `after`, `ary`, `assign`, `at`, `before`, `bind`, `bindAll`, `bindKey`,
* `callback`, `chain`, `chunk`, `commit`, `compact`, `concat`, `constant`,
* `countBy`, `create`, `curry`, `debounce`, `defaults`, `defer`, `delay`,
* `difference`, `drop`, `dropRight`, `dropRightWhile`, `dropWhile`, `fill`,
* `filter`, `flatten`, `flattenDeep`, `flow`, `flowRight`, `forEach`,
* `forEachRight`, `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `functions`,
* `groupBy`, `indexBy`, `initial`, `intersection`, `invert`, `invoke`, `keys`,
* `keysIn`, `map`, `mapValues`, `matches`, `memoize`, `merge`, `mixin`,
* `negate`, `noop`, `omit`, `once`, `pairs`, `partial`, `partialRight`,
* `partition`, `pick`, `plant`, `pluck`, `property`, `propertyOf`, `pull`,
* `pullAt`, `push`, `range`, `rearg`, `reject`, `remove`, `rest`, `reverse`,
* `shuffle`, `slice`, `sort`, `sortBy`, `sortByAll`, `splice`, `spread`,
* `take`, `takeRight`, `takeRightWhile`, `takeWhile`, `tap`, `throttle`,
* `thru`, `times`, `toArray`, `toPlainObject`, `transform`, `union`, `uniq`,
* `unshift`, `unzip`, `values`, `valuesIn`, `where`, `without`, `wrap`, `xor`,
* `zip`, and `zipObject`
*
* The wrapper methods that are **not** chainable by default are:
* `attempt`, `camelCase`, `capitalize`, `clone`, `cloneDeep`, `deburr`,
* `endsWith`, `escape`, `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`,
* `findLast`, `findLastIndex`, `findLastKey`, `findWhere`, `first`, `has`,
* `identity`, `includes`, `indexOf`, `isArguments`, `isArray`, `isBoolean`,
* `isDate`, `isElement`, `isEmpty`, `isEqual`, `isError`, `isFinite`,
* `isFunction`, `isMatch`, `isNative`, `isNaN`, `isNull`, `isNumber`,
* `isObject`, `isPlainObject`, `isRegExp`, `isString`, `isUndefined`,
* `isTypedArray`, `join`, `kebabCase`, `last`, `lastIndexOf`, `max`, `min`,
* `noConflict`, `now`, `pad`, `padLeft`, `padRight`, `parseInt`, `pop`,
* `random`, `reduce`, `reduceRight`, `repeat`, `result`, `runInContext`,
* `shift`, `size`, `snakeCase`, `some`, `sortedIndex`, `sortedLastIndex`,
* `startCase`, `startsWith`, `template`, `trim`, `trimLeft`, `trimRight`,
* `trunc`, `unescape`, `uniqueId`, `value`, and `words`
*
* The wrapper method `sample` will return a wrapped value when `n` is provided,
* otherwise an unwrapped value is returned.
*
* @name _
* @constructor
* @category Chain
* @param {*} value The value to wrap in a `lodash` instance.
* @returns {Object} Returns the new `lodash` wrapper instance.
* @example
*
* var wrapped = _([1, 2, 3]);
*
* // returns an unwrapped value
* wrapped.reduce(function(sum, n) { return sum + n; });
* // => 6
*
* // returns a wrapped value
* var squares = wrapped.map(function(n) { return n * n; });
*
* _.isArray(squares);
* // => false
*
* _.isArray(squares.value());
* // => true
*/
function lodash(value) {
if (isObjectLike(value) && !isArray(value) && !(value instanceof LazyWrapper)) {
if (value instanceof LodashWrapper) {
return value;
}
if (hasOwnProperty.call(value, '__chain__') && hasOwnProperty.call(value, '__wrapped__')) {
return wrapperClone(value);
}
}
return new LodashWrapper(value);
}
/**
* The base constructor for creating `lodash` wrapper objects.
*
* @private
* @param {*} value The value to wrap.
* @param {boolean} [chainAll] Enable chaining for all wrapper methods.
* @param {Array} [actions=[]] Actions to peform to resolve the unwrapped value.
*/
function LodashWrapper(value, chainAll, actions) {
this.__wrapped__ = value;
this.__actions__ = actions || [];
this.__chain__ = !!chainAll;
}
/**
* An object environment feature flags.
*
* @static
* @memberOf _
* @type Object
*/
var support = lodash.support = {};
(function(x) {
/**
* Detect if functions can be decompiled by `Function#toString`
* (all but Firefox OS certified apps, older Opera mobile browsers, and
* the PlayStation 3; forced `false` for Windows 8 apps).
*
* @memberOf _.support
* @type boolean
*/
support.funcDecomp = !isNative(context.WinRTError) && reThis.test(runInContext);
/**
* Detect if `Function#name` is supported (all but IE).
*
* @memberOf _.support
* @type boolean
*/
support.funcNames = typeof Function.name == 'string';
/**
* Detect if the DOM is supported.
*
* @memberOf _.support
* @type boolean
*/
try {
support.dom = document.createDocumentFragment().nodeType === 11;
} catch(e) {
support.dom = false;
}
/**
* Detect if `arguments` object indexes are non-enumerable.
*
* In Firefox < 4, IE < 9, PhantomJS, and Safari < 5.1 `arguments` object
* indexes are non-enumerable. Chrome < 25 and Node.js < 0.11.0 treat
* `arguments` object indexes as non-enumerable and fail `hasOwnProperty`
* checks for indexes that exceed their function's formal parameters with
* associated values of `0`.
*
* @memberOf _.support
* @type boolean
*/
try {
support.nonEnumArgs = !propertyIsEnumerable.call(arguments, 1);
} catch(e) {
support.nonEnumArgs = true;
}
}(0, 0));
/**
* By default, the template delimiters used by lodash are like those in
* embedded Ruby (ERB). Change the following template settings to use
* alternative delimiters.
*
* @static
* @memberOf _
* @type Object
*/
lodash.templateSettings = {
/**
* Used to detect `data` property values to be HTML-escaped.
*
* @memberOf _.templateSettings
* @type RegExp
*/
'escape': reEscape,
/**
* Used to detect code to be evaluated.
*
* @memberOf _.templateSettings
* @type RegExp
*/
'evaluate': reEvaluate,
/**
* Used to detect `data` property values to inject.
*
* @memberOf _.templateSettings
* @type RegExp
*/
'interpolate': reInterpolate,
/**
* Used to reference the data object in the template text.
*
* @memberOf _.templateSettings
* @type string
*/
'variable': '',
/**
* Used to import variables into the compiled template.
*
* @memberOf _.templateSettings
* @type Object
*/
'imports': {
/**
* A reference to the `lodash` function.
*
* @memberOf _.templateSettings.imports
* @type Function
*/
'_': lodash
}
};
/*------------------------------------------------------------------------*/
/**
* Creates a lazy wrapper object which wraps `value` to enable lazy evaluation.
*
* @private
* @param {*} value The value to wrap.
*/
function LazyWrapper(value) {
this.__wrapped__ = value;
this.__actions__ = null;
this.__dir__ = 1;
this.__dropCount__ = 0;
this.__filtered__ = false;
this.__iteratees__ = null;
this.__takeCount__ = POSITIVE_INFINITY;
this.__views__ = null;
}
/**
* Creates a clone of the lazy wrapper object.
*
* @private
* @name clone
* @memberOf LazyWrapper
* @returns {Object} Returns the cloned `LazyWrapper` object.
*/
function lazyClone() {
var actions = this.__actions__,
iteratees = this.__iteratees__,
views = this.__views__,
result = new LazyWrapper(this.__wrapped__);
result.__actions__ = actions ? arrayCopy(actions) : null;
result.__dir__ = this.__dir__;
result.__dropCount__ = this.__dropCount__;
result.__filtered__ = this.__filtered__;
result.__iteratees__ = iteratees ? arrayCopy(iteratees) : null;
result.__takeCount__ = this.__takeCount__;
result.__views__ = views ? arrayCopy(views) : null;
return result;
}
/**
* Reverses the direction of lazy iteration.
*
* @private
* @name reverse
* @memberOf LazyWrapper
* @returns {Object} Returns the new reversed `LazyWrapper` object.
*/
function lazyReverse() {
if (this.__filtered__) {
var result = new LazyWrapper(this);
result.__dir__ = -1;
result.__filtered__ = true;
} else {
result = this.clone();
result.__dir__ *= -1;
}
return result;
}
/**
* Extracts the unwrapped value from its lazy wrapper.
*
* @private
* @name value
* @memberOf LazyWrapper
* @returns {*} Returns the unwrapped value.
*/
function lazyValue() {
var array = this.__wrapped__.value();
if (!isArray(array)) {
return baseWrapperValue(array, this.__actions__);
}
var dir = this.__dir__,
isRight = dir < 0,
view = getView(0, array.length, this.__views__),
start = view.start,
end = view.end,
length = end - start,
dropCount = this.__dropCount__,
takeCount = nativeMin(length, this.__takeCount__),
index = isRight ? end : start - 1,
iteratees = this.__iteratees__,
iterLength = iteratees ? iteratees.length : 0,
resIndex = 0,
result = [];
outer:
while (length-- && resIndex < takeCount) {
index += dir;
var iterIndex = -1,
value = array[index];
while (++iterIndex < iterLength) {
var data = iteratees[iterIndex],
iteratee = data.iteratee,
computed = iteratee(value, index, array),
type = data.type;
if (type == LAZY_MAP_FLAG) {
value = computed;
} else if (!computed) {
if (type == LAZY_FILTER_FLAG) {
continue outer;
} else {
break outer;
}
}
}
if (dropCount) {
dropCount--;
} else {
result[resIndex++] = value;
}
}
return result;
}
/*------------------------------------------------------------------------*/
/**
* Creates a cache object to store key/value pairs.
*
* @private
* @static
* @name Cache
* @memberOf _.memoize
*/
function MapCache() {
this.__data__ = {};
}
/**
* Removes `key` and its value from the cache.
*
* @private
* @name delete
* @memberOf _.memoize.Cache
* @param {string} key The key of the value to remove.
* @returns {boolean} Returns `true` if the entry was removed successfully, else `false`.
*/
function mapDelete(key) {
return this.has(key) && delete this.__data__[key];
}
/**
* Gets the cached value for `key`.
*
* @private
* @name get
* @memberOf _.memoize.Cache
* @param {string} key The key of the value to get.
* @returns {*} Returns the cached value.
*/
function mapGet(key) {
return key == '__proto__' ? undefined : this.__data__[key];
}
/**
* Checks if a cached value for `key` exists.
*
* @private
* @name has
* @memberOf _.memoize.Cache
* @param {string} key The key of the entry to check.
* @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
*/
function mapHas(key) {
return key != '__proto__' && hasOwnProperty.call(this.__data__, key);
}
/**
* Adds `value` to `key` of the cache.
*
* @private
* @name set
* @memberOf _.memoize.Cache
* @param {string} key The key of the value to cache.
* @param {*} value The value to cache.
* @returns {Object} Returns the cache object.
*/
function mapSet(key, value) {
if (key != '__proto__') {
this.__data__[key] = value;
}
return this;
}
/*------------------------------------------------------------------------*/
/**
*
* Creates a cache object to store unique values.
*
* @private
* @param {Array} [values] The values to cache.
*/
function SetCache(values) {
var length = values ? values.length : 0;
this.data = { 'hash': nativeCreate(null), 'set': new Set };
while (length--) {
this.push(values[length]);
}
}
/**
* Checks if `value` is in `cache` mimicking the return signature of
* `_.indexOf` by returning `0` if the value is found, else `-1`.
*
* @private
* @param {Object} cache The cache to search.
* @param {*} value The value to search for.
* @returns {number} Returns `0` if `value` is found, else `-1`.
*/
function cacheIndexOf(cache, value) {
var data = cache.data,
result = (typeof value == 'string' || isObject(value)) ? data.set.has(value) : data.hash[value];
return result ? 0 : -1;
}
/**
* Adds `value` to the cache.
*
* @private
* @name push
* @memberOf SetCache
* @param {*} value The value to cache.
*/
function cachePush(value) {
var data = this.data;
if (typeof value == 'string' || isObject(value)) {
data.set.add(value);
} else {
data.hash[value] = true;
}
}
/*------------------------------------------------------------------------*/
/**
* Copies the values of `source` to `array`.
*
* @private
* @param {Array} source The array to copy values from.
* @param {Array} [array=[]] The array to copy values to.
* @returns {Array} Returns `array`.
*/
function arrayCopy(source, array) {
var index = -1,
length = source.length;
array || (array = Array(length));
while (++index < length) {
array[index] = source[index];
}
return array;
}
/**
* A specialized version of `_.forEach` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns `array`.
*/
function arrayEach(array, iteratee) {
var index = -1,
length = array.length;
while (++index < length) {
if (iteratee(array[index], index, array) === false) {
break;
}
}
return array;
}
/**
* A specialized version of `_.forEachRight` for arrays without support for
* callback shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns `array`.
*/
function arrayEachRight(array, iteratee) {
var length = array.length;
while (length--) {
if (iteratee(array[length], length, array) === false) {
break;
}
}
return array;
}
/**
* A specialized version of `_.every` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {boolean} Returns `true` if all elements pass the predicate check,
* else `false`.
*/
function arrayEvery(array, predicate) {
var index = -1,
length = array.length;
while (++index < length) {
if (!predicate(array[index], index, array)) {
return false;
}
}
return true;
}
/**
* A specialized version of `_.filter` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {Array} Returns the new filtered array.
*/
function arrayFilter(array, predicate) {
var index = -1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index];
if (predicate(value, index, array)) {
result[++resIndex] = value;
}
}
return result;
}
/**
* A specialized version of `_.map` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns the new mapped array.
*/
function arrayMap(array, iteratee) {
var index = -1,
length = array.length,
result = Array(length);
while (++index < length) {
result[index] = iteratee(array[index], index, array);
}
return result;
}
/**
* A specialized version of `_.max` for arrays without support for iteratees.
*
* @private
* @param {Array} array The array to iterate over.
* @returns {*} Returns the maximum value.
*/
function arrayMax(array) {
var index = -1,
length = array.length,
result = NEGATIVE_INFINITY;
while (++index < length) {
var value = array[index];
if (value > result) {
result = value;
}
}
return result;
}
/**
* A specialized version of `_.min` for arrays without support for iteratees.
*
* @private
* @param {Array} array The array to iterate over.
* @returns {*} Returns the minimum value.
*/
function arrayMin(array) {
var index = -1,
length = array.length,
result = POSITIVE_INFINITY;
while (++index < length) {
var value = array[index];
if (value < result) {
result = value;
}
}
return result;
}
/**
* A specialized version of `_.reduce` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {boolean} [initFromArray] Specify using the first element of `array`
* as the initial value.
* @returns {*} Returns the accumulated value.
*/
function arrayReduce(array, iteratee, accumulator, initFromArray) {
var index = -1,
length = array.length;
if (initFromArray && length) {
accumulator = array[++index];
}
while (++index < length) {
accumulator = iteratee(accumulator, array[index], index, array);
}
return accumulator;
}
/**
* A specialized version of `_.reduceRight` for arrays without support for
* callback shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {boolean} [initFromArray] Specify using the last element of `array`
* as the initial value.
* @returns {*} Returns the accumulated value.
*/
function arrayReduceRight(array, iteratee, accumulator, initFromArray) {
var length = array.length;
if (initFromArray && length) {
accumulator = array[--length];
}
while (length--) {
accumulator = iteratee(accumulator, array[length], length, array);
}
return accumulator;
}
/**
* A specialized version of `_.some` for arrays without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array} array The array to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {boolean} Returns `true` if any element passes the predicate check,
* else `false`.
*/
function arraySome(array, predicate) {
var index = -1,
length = array.length;
while (++index < length) {
if (predicate(array[index], index, array)) {
return true;
}
}
return false;
}
/**
* Used by `_.defaults` to customize its `_.assign` use.
*
* @private
* @param {*} objectValue The destination object property value.
* @param {*} sourceValue The source object property value.
* @returns {*} Returns the value to assign to the destination object.
*/
function assignDefaults(objectValue, sourceValue) {
return typeof objectValue == 'undefined' ? sourceValue : objectValue;
}
/**
* Used by `_.template` to customize its `_.assign` use.
*
* **Note:** This method is like `assignDefaults` except that it ignores
* inherited property values when checking if a property is `undefined`.
*
* @private
* @param {*} objectValue The destination object property value.
* @param {*} sourceValue The source object property value.
* @param {string} key The key associated with the object and source values.
* @param {Object} object The destination object.
* @returns {*} Returns the value to assign to the destination object.
*/
function assignOwnDefaults(objectValue, sourceValue, key, object) {
return (typeof objectValue == 'undefined' || !hasOwnProperty.call(object, key))
? sourceValue
: objectValue;
}
/**
* The base implementation of `_.assign` without support for argument juggling,
* multiple sources, and `this` binding `customizer` functions.
*
* @private
* @param {Object} object The destination object.
* @param {Object} source The source object.
* @param {Function} [customizer] The function to customize assigning values.
* @returns {Object} Returns the destination object.
*/
function baseAssign(object, source, customizer) {
var props = keys(source);
if (!customizer) {
return baseCopy(source, object, props);
}
var index = -1,
length = props.length;
while (++index < length) {
var key = props[index],
value = object[key],
result = customizer(value, source[key], key, object, source);
if ((result === result ? result !== value : value === value) ||
(typeof value == 'undefined' && !(key in object))) {
object[key] = result;
}
}
return object;
}
/**
* The base implementation of `_.at` without support for strings and individual
* key arguments.
*
* @private
* @param {Array|Object} collection The collection to iterate over.
* @param {number[]|string[]} [props] The property names or indexes of elements to pick.
* @returns {Array} Returns the new array of picked elements.
*/
function baseAt(collection, props) {
var index = -1,
length = collection.length,
isArr = isLength(length),
propsLength = props.length,
result = Array(propsLength);
while(++index < propsLength) {
var key = props[index];
if (isArr) {
key = parseFloat(key);
result[index] = isIndex(key, length) ? collection[key] : undefined;
} else {
result[index] = collection[key];
}
}
return result;
}
/**
* Copies the properties of `source` to `object`.
*
* @private
* @param {Object} source The object to copy properties from.
* @param {Object} [object={}] The object to copy properties to.
* @param {Array} props The property names to copy.
* @returns {Object} Returns `object`.
*/
function baseCopy(source, object, props) {
if (!props) {
props = object;
object = {};
}
var index = -1,
length = props.length;
while (++index < length) {
var key = props[index];
object[key] = source[key];
}
return object;
}
/**
* The base implementation of `_.bindAll` without support for individual
* method name arguments.
*
* @private
* @param {Object} object The object to bind and assign the bound methods to.
* @param {string[]} methodNames The object method names to bind.
* @returns {Object} Returns `object`.
*/
function baseBindAll(object, methodNames) {
var index = -1,
length = methodNames.length;
while (++index < length) {
var key = methodNames[index];
object[key] = createWrapper(object[key], BIND_FLAG, object);
}
return object;
}
/**
* The base implementation of `_.callback` which supports specifying the
* number of arguments to provide to `func`.
*
* @private
* @param {*} [func=_.identity] The value to convert to a callback.
* @param {*} [thisArg] The `this` binding of `func`.
* @param {number} [argCount] The number of arguments to provide to `func`.
* @returns {Function} Returns the callback.
*/
function baseCallback(func, thisArg, argCount) {
var type = typeof func;
if (type == 'function') {
return (typeof thisArg != 'undefined' && isBindable(func))
? bindCallback(func, thisArg, argCount)
: func;
}
if (func == null) {
return identity;
}
if (type == 'object') {
return baseMatches(func);
}
return typeof thisArg == 'undefined'
? baseProperty(func + '')
: baseMatchesProperty(func + '', thisArg);
}
/**
* The base implementation of `_.clone` without support for argument juggling
* and `this` binding `customizer` functions.
*
* @private
* @param {*} value The value to clone.
* @param {boolean} [isDeep] Specify a deep clone.
* @param {Function} [customizer] The function to customize cloning values.
* @param {string} [key] The key of `value`.
* @param {Object} [object] The object `value` belongs to.
* @param {Array} [stackA=[]] Tracks traversed source objects.
* @param {Array} [stackB=[]] Associates clones with source counterparts.
* @returns {*} Returns the cloned value.
*/
function baseClone(value, isDeep, customizer, key, object, stackA, stackB) {
var result;
if (customizer) {
result = object ? customizer(value, key, object) : customizer(value);
}
if (typeof result != 'undefined') {
return result;
}
if (!isObject(value)) {
return value;
}
var isArr = isArray(value);
if (isArr) {
result = initCloneArray(value);
if (!isDeep) {
return arrayCopy(value, result);
}
} else {
var tag = objToString.call(value),
isFunc = tag == funcTag;
if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
result = initCloneObject(isFunc ? {} : value);
if (!isDeep) {
return baseCopy(value, result, keys(value));
}
} else {
return cloneableTags[tag]
? initCloneByTag(value, tag, isDeep)
: (object ? value : {});
}
}
// Check for circular references and return corresponding clone.
stackA || (stackA = []);
stackB || (stackB = []);
var length = stackA.length;
while (length--) {
if (stackA[length] == value) {
return stackB[length];
}
}
// Add the source value to the stack of traversed objects and associate it with its clone.
stackA.push(value);
stackB.push(result);
// Recursively populate clone (susceptible to call stack limits).
(isArr ? arrayEach : baseForOwn)(value, function(subValue, key) {
result[key] = baseClone(subValue, isDeep, customizer, key, value, stackA, stackB);
});
return result;
}
/**
* The base implementation of `_.create` without support for assigning
* properties to the created object.
*
* @private
* @param {Object} prototype The object to inherit from.
* @returns {Object} Returns the new object.
*/
var baseCreate = (function() {
function Object() {}
return function(prototype) {
if (isObject(prototype)) {
Object.prototype = prototype;
var result = new Object;
Object.prototype = null;
}
return result || context.Object();
};
}());
/**
* The base implementation of `_.delay` and `_.defer` which accepts an index
* of where to slice the arguments to provide to `func`.
*
* @private
* @param {Function} func The function to delay.
* @param {number} wait The number of milliseconds to delay invocation.
* @param {Object} args The `arguments` object to slice and provide to `func`.
* @returns {number} Returns the timer id.
*/
function baseDelay(func, wait, args, fromIndex) {
if (typeof func != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
return setTimeout(function() { func.apply(undefined, baseSlice(args, fromIndex)); }, wait);
}
/**
* The base implementation of `_.difference` which accepts a single array
* of values to exclude.
*
* @private
* @param {Array} array The array to inspect.
* @param {Array} values The values to exclude.
* @returns {Array} Returns the new array of filtered values.
*/
function baseDifference(array, values) {
var length = array ? array.length : 0,
result = [];
if (!length) {
return result;
}
var index = -1,
indexOf = getIndexOf(),
isCommon = indexOf == baseIndexOf,
cache = isCommon && values.length >= 200 && createCache(values),
valuesLength = values.length;
if (cache) {
indexOf = cacheIndexOf;
isCommon = false;
values = cache;
}
outer:
while (++index < length) {
var value = array[index];
if (isCommon && value === value) {
var valuesIndex = valuesLength;
while (valuesIndex--) {
if (values[valuesIndex] === value) {
continue outer;
}
}
result.push(value);
}
else if (indexOf(values, value) < 0) {
result.push(value);
}
}
return result;
}
/**
* The base implementation of `_.forEach` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array|Object|string} Returns `collection`.
*/
function baseEach(collection, iteratee) {
var length = collection ? collection.length : 0;
if (!isLength(length)) {
return baseForOwn(collection, iteratee);
}
var index = -1,
iterable = toObject(collection);
while (++index < length) {
if (iteratee(iterable[index], index, iterable) === false) {
break;
}
}
return collection;
}
/**
* The base implementation of `_.forEachRight` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array|Object|string} Returns `collection`.
*/
function baseEachRight(collection, iteratee) {
var length = collection ? collection.length : 0;
if (!isLength(length)) {
return baseForOwnRight(collection, iteratee);
}
var iterable = toObject(collection);
while (length--) {
if (iteratee(iterable[length], length, iterable) === false) {
break;
}
}
return collection;
}
/**
* The base implementation of `_.every` without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {boolean} Returns `true` if all elements pass the predicate check,
* else `false`
*/
function baseEvery(collection, predicate) {
var result = true;
baseEach(collection, function(value, index, collection) {
result = !!predicate(value, index, collection);
return result;
});
return result;
}
/**
* The base implementation of `_.fill` without an iteratee call guard.
*
* @private
* @param {Array} array The array to fill.
* @param {*} value The value to fill `array` with.
* @param {number} [start=0] The start position.
* @param {number} [end=array.length] The end position.
* @returns {Array} Returns `array`.
*/
function baseFill(array, value, start, end) {
var length = array.length;
start = start == null ? 0 : (+start || 0);
if (start < 0) {
start = -start > length ? 0 : (length + start);
}
end = (typeof end == 'undefined' || end > length) ? length : (+end || 0);
if (end < 0) {
end += length;
}
length = start > end ? 0 : end >>> 0;
start >>>= 0;
while (start < length) {
array[start++] = value;
}
return array;
}
/**
* The base implementation of `_.filter` without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {Array} Returns the new filtered array.
*/
function baseFilter(collection, predicate) {
var result = [];
baseEach(collection, function(value, index, collection) {
if (predicate(value, index, collection)) {
result.push(value);
}
});
return result;
}
/**
* The base implementation of `_.find`, `_.findLast`, `_.findKey`, and `_.findLastKey`,
* without support for callback shorthands and `this` binding, which iterates
* over `collection` using the provided `eachFunc`.
*
* @private
* @param {Array|Object|string} collection The collection to search.
* @param {Function} predicate The function invoked per iteration.
* @param {Function} eachFunc The function to iterate over `collection`.
* @param {boolean} [retKey] Specify returning the key of the found element
* instead of the element itself.
* @returns {*} Returns the found element or its key, else `undefined`.
*/
function baseFind(collection, predicate, eachFunc, retKey) {
var result;
eachFunc(collection, function(value, key, collection) {
if (predicate(value, key, collection)) {
result = retKey ? key : value;
return false;
}
});
return result;
}
/**
* The base implementation of `_.flatten` with added support for restricting
* flattening and specifying the start index.
*
* @private
* @param {Array} array The array to flatten.
* @param {boolean} [isDeep] Specify a deep flatten.
* @param {boolean} [isStrict] Restrict flattening to arrays and `arguments` objects.
* @param {number} [fromIndex=0] The index to start from.
* @returns {Array} Returns the new flattened array.
*/
function baseFlatten(array, isDeep, isStrict, fromIndex) {
var index = (fromIndex || 0) - 1,
length = array.length,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index];
if (isObjectLike(value) && isLength(value.length) && (isArray(value) || isArguments(value))) {
if (isDeep) {
// Recursively flatten arrays (susceptible to call stack limits).
value = baseFlatten(value, isDeep, isStrict);
}
var valIndex = -1,
valLength = value.length;
result.length += valLength;
while (++valIndex < valLength) {
result[++resIndex] = value[valIndex];
}
} else if (!isStrict) {
result[++resIndex] = value;
}
}
return result;
}
/**
* The base implementation of `baseForIn` and `baseForOwn` which iterates
* over `object` properties returned by `keysFunc` invoking `iteratee` for
* each property. Iterator functions may exit iteration early by explicitly
* returning `false`.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {Function} keysFunc The function to get the keys of `object`.
* @returns {Object} Returns `object`.
*/
function baseFor(object, iteratee, keysFunc) {
var index = -1,
iterable = toObject(object),
props = keysFunc(object),
length = props.length;
while (++index < length) {
var key = props[index];
if (iteratee(iterable[key], key, iterable) === false) {
break;
}
}
return object;
}
/**
* This function is like `baseFor` except that it iterates over properties
* in the opposite order.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {Function} keysFunc The function to get the keys of `object`.
* @returns {Object} Returns `object`.
*/
function baseForRight(object, iteratee, keysFunc) {
var iterable = toObject(object),
props = keysFunc(object),
length = props.length;
while (length--) {
var key = props[length];
if (iteratee(iterable[key], key, iterable) === false) {
break;
}
}
return object;
}
/**
* The base implementation of `_.forIn` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Object} Returns `object`.
*/
function baseForIn(object, iteratee) {
return baseFor(object, iteratee, keysIn);
}
/**
* The base implementation of `_.forOwn` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Object} Returns `object`.
*/
function baseForOwn(object, iteratee) {
return baseFor(object, iteratee, keys);
}
/**
* The base implementation of `_.forOwnRight` without support for callback
* shorthands and `this` binding.
*
* @private
* @param {Object} object The object to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Object} Returns `object`.
*/
function baseForOwnRight(object, iteratee) {
return baseForRight(object, iteratee, keys);
}
/**
* The base implementation of `_.functions` which creates an array of
* `object` function property names filtered from those provided.
*
* @private
* @param {Object} object The object to inspect.
* @param {Array} props The property names to filter.
* @returns {Array} Returns the new array of filtered property names.
*/
function baseFunctions(object, props) {
var index = -1,
length = props.length,
resIndex = -1,
result = [];
while (++index < length) {
var key = props[index];
if (isFunction(object[key])) {
result[++resIndex] = key;
}
}
return result;
}
/**
* The base implementation of `_.invoke` which requires additional arguments
* to be provided as an array of arguments rather than individually.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|string} methodName The name of the method to invoke or
* the function invoked per iteration.
* @param {Array} [args] The arguments to invoke the method with.
* @returns {Array} Returns the array of results.
*/
function baseInvoke(collection, methodName, args) {
var index = -1,
isFunc = typeof methodName == 'function',
length = collection ? collection.length : 0,
result = isLength(length) ? Array(length) : [];
baseEach(collection, function(value) {
var func = isFunc ? methodName : (value != null && value[methodName]);
result[++index] = func ? func.apply(value, args) : undefined;
});
return result;
}
/**
* The base implementation of `_.isEqual` without support for `this` binding
* `customizer` functions.
*
* @private
* @param {*} value The value to compare.
* @param {*} other The other value to compare.
* @param {Function} [customizer] The function to customize comparing values.
* @param {boolean} [isWhere] Specify performing partial comparisons.
* @param {Array} [stackA] Tracks traversed `value` objects.
* @param {Array} [stackB] Tracks traversed `other` objects.
* @returns {boolean} Returns `true` if the values are equivalent, else `false`.
*/
function baseIsEqual(value, other, customizer, isWhere, stackA, stackB) {
// Exit early for identical values.
if (value === other) {
// Treat `+0` vs. `-0` as not equal.
return value !== 0 || (1 / value == 1 / other);
}
var valType = typeof value,
othType = typeof other;
// Exit early for unlike primitive values.
if ((valType != 'function' && valType != 'object' && othType != 'function' && othType != 'object') ||
value == null || other == null) {
// Return `false` unless both values are `NaN`.
return value !== value && other !== other;
}
return baseIsEqualDeep(value, other, baseIsEqual, customizer, isWhere, stackA, stackB);
}
/**
* A specialized version of `baseIsEqual` for arrays and objects which performs
* deep comparisons and tracks traversed objects enabling objects with circular
* references to be compared.
*
* @private
* @param {Object} object The object to compare.
* @param {Object} other The other object to compare.
* @param {Function} equalFunc The function to determine equivalents of values.
* @param {Function} [customizer] The function to customize comparing objects.
* @param {boolean} [isWhere] Specify performing partial comparisons.
* @param {Array} [stackA=[]] Tracks traversed `value` objects.
* @param {Array} [stackB=[]] Tracks traversed `other` objects.
* @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
*/
function baseIsEqualDeep(object, other, equalFunc, customizer, isWhere, stackA, stackB) {
var objIsArr = isArray(object),
othIsArr = isArray(other),
objTag = arrayTag,
othTag = arrayTag;
if (!objIsArr) {
objTag = objToString.call(object);
if (objTag == argsTag) {
objTag = objectTag;
} else if (objTag != objectTag) {
objIsArr = isTypedArray(object);
}
}
if (!othIsArr) {
othTag = objToString.call(other);
if (othTag == argsTag) {
othTag = objectTag;
} else if (othTag != objectTag) {
othIsArr = isTypedArray(other);
}
}
var objIsObj = objTag == objectTag,
othIsObj = othTag == objectTag,
isSameTag = objTag == othTag;
if (isSameTag && !(objIsArr || objIsObj)) {
return equalByTag(object, other, objTag);
}
var valWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
othWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');
if (valWrapped || othWrapped) {
return equalFunc(valWrapped ? object.value() : object, othWrapped ? other.value() : other, customizer, isWhere, stackA, stackB);
}
if (!isSameTag) {
return false;
}
// Assume cyclic values are equal.
// For more information on detecting circular references see https://es5.github.io/#JO.
stackA || (stackA = []);
stackB || (stackB = []);
var length = stackA.length;
while (length--) {
if (stackA[length] == object) {
return stackB[length] == other;
}
}
// Add `object` and `other` to the stack of traversed objects.
stackA.push(object);
stackB.push(other);
var result = (objIsArr ? equalArrays : equalObjects)(object, other, equalFunc, customizer, isWhere, stackA, stackB);
stackA.pop();
stackB.pop();
return result;
}
/**
* The base implementation of `_.isMatch` without support for callback
* shorthands or `this` binding.
*
* @private
* @param {Object} object The object to inspect.
* @param {Array} props The source property names to match.
* @param {Array} values The source values to match.
* @param {Array} strictCompareFlags Strict comparison flags for source values.
* @param {Function} [customizer] The function to customize comparing objects.
* @returns {boolean} Returns `true` if `object` is a match, else `false`.
*/
function baseIsMatch(object, props, values, strictCompareFlags, customizer) {
var length = props.length;
if (object == null) {
return !length;
}
var index = -1,
noCustomizer = !customizer;
while (++index < length) {
if ((noCustomizer && strictCompareFlags[index])
? values[index] !== object[props[index]]
: !hasOwnProperty.call(object, props[index])
) {
return false;
}
}
index = -1;
while (++index < length) {
var key = props[index];
if (noCustomizer && strictCompareFlags[index]) {
var result = hasOwnProperty.call(object, key);
} else {
var objValue = object[key],
srcValue = values[index];
result = customizer ? customizer(objValue, srcValue, key) : undefined;
if (typeof result == 'undefined') {
result = baseIsEqual(srcValue, objValue, customizer, true);
}
}
if (!result) {
return false;
}
}
return true;
}
/**
* The base implementation of `_.map` without support for callback shorthands
* or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @returns {Array} Returns the new mapped array.
*/
function baseMap(collection, iteratee) {
var result = [];
baseEach(collection, function(value, key, collection) {
result.push(iteratee(value, key, collection));
});
return result;
}
/**
* The base implementation of `_.matches` which does not clone `source`.
*
* @private
* @param {Object} source The object of property values to match.
* @returns {Function} Returns the new function.
*/
function baseMatches(source) {
var props = keys(source),
length = props.length;
if (length == 1) {
var key = props[0],
value = source[key];
if (isStrictComparable(value)) {
return function(object) {
return object != null && value === object[key] && hasOwnProperty.call(object, key);
};
}
}
var values = Array(length),
strictCompareFlags = Array(length);
while (length--) {
value = source[props[length]];
values[length] = value;
strictCompareFlags[length] = isStrictComparable(value);
}
return function(object) {
return baseIsMatch(object, props, values, strictCompareFlags);
};
}
/**
* The base implementation of `_.matchesProperty` which does not coerce `key`
* to a string.
*
* @private
* @param {string} key The key of the property to get.
* @param {*} value The value to compare.
* @returns {Function} Returns the new function.
*/
function baseMatchesProperty(key, value) {
if (isStrictComparable(value)) {
return function(object) {
return object != null && object[key] === value;
};
}
return function(object) {
return object != null && baseIsEqual(value, object[key], null, true);
};
}
/**
* The base implementation of `_.merge` without support for argument juggling,
* multiple sources, and `this` binding `customizer` functions.
*
* @private
* @param {Object} object The destination object.
* @param {Object} source The source object.
* @param {Function} [customizer] The function to customize merging properties.
* @param {Array} [stackA=[]] Tracks traversed source objects.
* @param {Array} [stackB=[]] Associates values with source counterparts.
* @returns {Object} Returns the destination object.
*/
function baseMerge(object, source, customizer, stackA, stackB) {
var isSrcArr = isLength(source.length) && (isArray(source) || isTypedArray(source));
(isSrcArr ? arrayEach : baseForOwn)(source, function(srcValue, key, source) {
if (isObjectLike(srcValue)) {
stackA || (stackA = []);
stackB || (stackB = []);
return baseMergeDeep(object, source, key, baseMerge, customizer, stackA, stackB);
}
var value = object[key],
result = customizer ? customizer(value, srcValue, key, object, source) : undefined,
isCommon = typeof result == 'undefined';
if (isCommon) {
result = srcValue;
}
if ((isSrcArr || typeof result != 'undefined') &&
(isCommon || (result === result ? result !== value : value === value))) {
object[key] = result;
}
});
return object;
}
/**
* A specialized version of `baseMerge` for arrays and objects which performs
* deep merges and tracks traversed objects enabling objects with circular
* references to be merged.
*
* @private
* @param {Object} object The destination object.
* @param {Object} source The source object.
* @param {string} key The key of the value to merge.
* @param {Function} mergeFunc The function to merge values.
* @param {Function} [customizer] The function to customize merging properties.
* @param {Array} [stackA=[]] Tracks traversed source objects.
* @param {Array} [stackB=[]] Associates values with source counterparts.
* @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
*/
function baseMergeDeep(object, source, key, mergeFunc, customizer, stackA, stackB) {
var length = stackA.length,
srcValue = source[key];
while (length--) {
if (stackA[length] == srcValue) {
object[key] = stackB[length];
return;
}
}
var value = object[key],
result = customizer ? customizer(value, srcValue, key, object, source) : undefined,
isCommon = typeof result == 'undefined';
if (isCommon) {
result = srcValue;
if (isLength(srcValue.length) && (isArray(srcValue) || isTypedArray(srcValue))) {
result = isArray(value)
? value
: (value ? arrayCopy(value) : []);
}
else if (isPlainObject(srcValue) || isArguments(srcValue)) {
result = isArguments(value)
? toPlainObject(value)
: (isPlainObject(value) ? value : {});
}
else {
isCommon = false;
}
}
// Add the source value to the stack of traversed objects and associate
// it with its merged value.
stackA.push(srcValue);
stackB.push(result);
if (isCommon) {
// Recursively merge objects and arrays (susceptible to call stack limits).
object[key] = mergeFunc(result, srcValue, customizer, stackA, stackB);
} else if (result === result ? result !== value : value === value) {
object[key] = result;
}
}
/**
* The base implementation of `_.property` which does not coerce `key` to a string.
*
* @private
* @param {string} key The key of the property to get.
* @returns {Function} Returns the new function.
*/
function baseProperty(key) {
return function(object) {
return object == null ? undefined : object[key];
};
}
/**
* The base implementation of `_.pullAt` without support for individual
* index arguments.
*
* @private
* @param {Array} array The array to modify.
* @param {number[]} indexes The indexes of elements to remove.
* @returns {Array} Returns the new array of removed elements.
*/
function basePullAt(array, indexes) {
var length = indexes.length,
result = baseAt(array, indexes);
indexes.sort(baseCompareAscending);
while (length--) {
var index = parseFloat(indexes[length]);
if (index != previous && isIndex(index)) {
var previous = index;
splice.call(array, index, 1);
}
}
return result;
}
/**
* The base implementation of `_.random` without support for argument juggling
* and returning floating-point numbers.
*
* @private
* @param {number} min The minimum possible value.
* @param {number} max The maximum possible value.
* @returns {number} Returns the random number.
*/
function baseRandom(min, max) {
return min + floor(nativeRandom() * (max - min + 1));
}
/**
* The base implementation of `_.reduce` and `_.reduceRight` without support
* for callback shorthands or `this` binding, which iterates over `collection`
* using the provided `eachFunc`.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {*} accumulator The initial value.
* @param {boolean} initFromCollection Specify using the first or last element
* of `collection` as the initial value.
* @param {Function} eachFunc The function to iterate over `collection`.
* @returns {*} Returns the accumulated value.
*/
function baseReduce(collection, iteratee, accumulator, initFromCollection, eachFunc) {
eachFunc(collection, function(value, index, collection) {
accumulator = initFromCollection
? (initFromCollection = false, value)
: iteratee(accumulator, value, index, collection);
});
return accumulator;
}
/**
* The base implementation of `setData` without support for hot loop detection.
*
* @private
* @param {Function} func The function to associate metadata with.
* @param {*} data The metadata.
* @returns {Function} Returns `func`.
*/
var baseSetData = !metaMap ? identity : function(func, data) {
metaMap.set(func, data);
return func;
};
/**
* The base implementation of `_.slice` without an iteratee call guard.
*
* @private
* @param {Array} array The array to slice.
* @param {number} [start=0] The start position.
* @param {number} [end=array.length] The end position.
* @returns {Array} Returns the slice of `array`.
*/
function baseSlice(array, start, end) {
var index = -1,
length = array.length;
start = start == null ? 0 : (+start || 0);
if (start < 0) {
start = -start > length ? 0 : (length + start);
}
end = (typeof end == 'undefined' || end > length) ? length : (+end || 0);
if (end < 0) {
end += length;
}
length = start > end ? 0 : (end - start) >>> 0;
start >>>= 0;
var result = Array(length);
while (++index < length) {
result[index] = array[index + start];
}
return result;
}
/**
* The base implementation of `_.some` without support for callback shorthands
* or `this` binding.
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} predicate The function invoked per iteration.
* @returns {boolean} Returns `true` if any element passes the predicate check,
* else `false`.
*/
function baseSome(collection, predicate) {
var result;
baseEach(collection, function(value, index, collection) {
result = predicate(value, index, collection);
return !result;
});
return !!result;
}
/**
* The base implementation of `_.uniq` without support for callback shorthands
* and `this` binding.
*
* @private
* @param {Array} array The array to inspect.
* @param {Function} [iteratee] The function invoked per iteration.
* @returns {Array} Returns the new duplicate-value-free array.
*/
function baseUniq(array, iteratee) {
var index = -1,
indexOf = getIndexOf(),
length = array.length,
isCommon = indexOf == baseIndexOf,
isLarge = isCommon && length >= 200,
seen = isLarge && createCache(),
result = [];
if (seen) {
indexOf = cacheIndexOf;
isCommon = false;
} else {
isLarge = false;
seen = iteratee ? [] : result;
}
outer:
while (++index < length) {
var value = array[index],
computed = iteratee ? iteratee(value, index, array) : value;
if (isCommon && value === value) {
var seenIndex = seen.length;
while (seenIndex--) {
if (seen[seenIndex] === computed) {
continue outer;
}
}
if (iteratee) {
seen.push(computed);
}
result.push(value);
}
else if (indexOf(seen, computed) < 0) {
if (iteratee || isLarge) {
seen.push(computed);
}
result.push(value);
}
}
return result;
}
/**
* The base implementation of `_.values` and `_.valuesIn` which creates an
* array of `object` property values corresponding to the property names
* returned by `keysFunc`.
*
* @private
* @param {Object} object The object to query.
* @param {Array} props The property names to get values for.
* @returns {Object} Returns the array of property values.
*/
function baseValues(object, props) {
var index = -1,
length = props.length,
result = Array(length);
while (++index < length) {
result[index] = object[props[index]];
}
return result;
}
/**
* The base implementation of `wrapperValue` which returns the result of
* performing a sequence of actions on the unwrapped `value`, where each
* successive action is supplied the return value of the previous.
*
* @private
* @param {*} value The unwrapped value.
* @param {Array} actions Actions to peform to resolve the unwrapped value.
* @returns {*} Returns the resolved unwrapped value.
*/
function baseWrapperValue(value, actions) {
var result = value;
if (result instanceof LazyWrapper) {
result = result.value();
}
var index = -1,
length = actions.length;
while (++index < length) {
var args = [result],
action = actions[index];
push.apply(args, action.args);
result = action.func.apply(action.thisArg, args);
}
return result;
}
/**
* Performs a binary search of `array` to determine the index at which `value`
* should be inserted into `array` in order to maintain its sort order.
*
* @private
* @param {Array} array The sorted array to inspect.
* @param {*} value The value to evaluate.
* @param {boolean} [retHighest] Specify returning the highest, instead
* of the lowest, index at which a value should be inserted into `array`.
* @returns {number} Returns the index at which `value` should be inserted
* into `array`.
*/
function binaryIndex(array, value, retHighest) {
var low = 0,
high = array ? array.length : low;
if (typeof value == 'number' && value === value && high <= HALF_MAX_ARRAY_LENGTH) {
while (low < high) {
var mid = (low + high) >>> 1,
computed = array[mid];
if (retHighest ? (computed <= value) : (computed < value)) {
low = mid + 1;
} else {
high = mid;
}
}
return high;
}
return binaryIndexBy(array, value, identity, retHighest);
}
/**
* This function is like `binaryIndex` except that it invokes `iteratee` for
* `value` and each element of `array` to compute their sort ranking. The
* iteratee is invoked with one argument; (value).
*
* @private
* @param {Array} array The sorted array to inspect.
* @param {*} value The value to evaluate.
* @param {Function} iteratee The function invoked per iteration.
* @param {boolean} [retHighest] Specify returning the highest, instead
* of the lowest, index at which a value should be inserted into `array`.
* @returns {number} Returns the index at which `value` should be inserted
* into `array`.
*/
function binaryIndexBy(array, value, iteratee, retHighest) {
value = iteratee(value);
var low = 0,
high = array ? array.length : 0,
valIsNaN = value !== value,
valIsUndef = typeof value == 'undefined';
while (low < high) {
var mid = floor((low + high) / 2),
computed = iteratee(array[mid]),
isReflexive = computed === computed;
if (valIsNaN) {
var setLow = isReflexive || retHighest;
} else if (valIsUndef) {
setLow = isReflexive && (retHighest || typeof computed != 'undefined');
} else {
setLow = retHighest ? (computed <= value) : (computed < value);
}
if (setLow) {
low = mid + 1;
} else {
high = mid;
}
}
return nativeMin(high, MAX_ARRAY_INDEX);
}
/**
* A specialized version of `baseCallback` which only supports `this` binding
* and specifying the number of arguments to provide to `func`.
*
* @private
* @param {Function} func The function to bind.
* @param {*} thisArg The `this` binding of `func`.
* @param {number} [argCount] The number of arguments to provide to `func`.
* @returns {Function} Returns the callback.
*/
function bindCallback(func, thisArg, argCount) {
if (typeof func != 'function') {
return identity;
}
if (typeof thisArg == 'undefined') {
return func;
}
switch (argCount) {
case 1: return function(value) {
return func.call(thisArg, value);
};
case 3: return function(value, index, collection) {
return func.call(thisArg, value, index, collection);
};
case 4: return function(accumulator, value, index, collection) {
return func.call(thisArg, accumulator, value, index, collection);
};
case 5: return function(value, other, key, object, source) {
return func.call(thisArg, value, other, key, object, source);
};
}
return function() {
return func.apply(thisArg, arguments);
};
}
/**
* Creates a clone of the given array buffer.
*
* @private
* @param {ArrayBuffer} buffer The array buffer to clone.
* @returns {ArrayBuffer} Returns the cloned array buffer.
*/
function bufferClone(buffer) {
return bufferSlice.call(buffer, 0);
}
if (!bufferSlice) {
// PhantomJS has `ArrayBuffer` and `Uint8Array` but not `Float64Array`.
bufferClone = !(ArrayBuffer && Uint8Array) ? constant(null) : function(buffer) {
var byteLength = buffer.byteLength,
floatLength = Float64Array ? floor(byteLength / FLOAT64_BYTES_PER_ELEMENT) : 0,
offset = floatLength * FLOAT64_BYTES_PER_ELEMENT,
result = new ArrayBuffer(byteLength);
if (floatLength) {
var view = new Float64Array(result, 0, floatLength);
view.set(new Float64Array(buffer, 0, floatLength));
}
if (byteLength != offset) {
view = new Uint8Array(result, offset);
view.set(new Uint8Array(buffer, offset));
}
return result;
};
}
/**
* Creates an array that is the composition of partially applied arguments,
* placeholders, and provided arguments into a single array of arguments.
*
* @private
* @param {Array|Object} args The provided arguments.
* @param {Array} partials The arguments to prepend to those provided.
* @param {Array} holders The `partials` placeholder indexes.
* @returns {Array} Returns the new array of composed arguments.
*/
function composeArgs(args, partials, holders) {
var holdersLength = holders.length,
argsIndex = -1,
argsLength = nativeMax(args.length - holdersLength, 0),
leftIndex = -1,
leftLength = partials.length,
result = Array(argsLength + leftLength);
while (++leftIndex < leftLength) {
result[leftIndex] = partials[leftIndex];
}
while (++argsIndex < holdersLength) {
result[holders[argsIndex]] = args[argsIndex];
}
while (argsLength--) {
result[leftIndex++] = args[argsIndex++];
}
return result;
}
/**
* This function is like `composeArgs` except that the arguments composition
* is tailored for `_.partialRight`.
*
* @private
* @param {Array|Object} args The provided arguments.
* @param {Array} partials The arguments to append to those provided.
* @param {Array} holders The `partials` placeholder indexes.
* @returns {Array} Returns the new array of composed arguments.
*/
function composeArgsRight(args, partials, holders) {
var holdersIndex = -1,
holdersLength = holders.length,
argsIndex = -1,
argsLength = nativeMax(args.length - holdersLength, 0),
rightIndex = -1,
rightLength = partials.length,
result = Array(argsLength + rightLength);
while (++argsIndex < argsLength) {
result[argsIndex] = args[argsIndex];
}
var pad = argsIndex;
while (++rightIndex < rightLength) {
result[pad + rightIndex] = partials[rightIndex];
}
while (++holdersIndex < holdersLength) {
result[pad + holders[holdersIndex]] = args[argsIndex++];
}
return result;
}
/**
* Creates a function that aggregates a collection, creating an accumulator
* object composed from the results of running each element in the collection
* through an iteratee.
*
* @private
* @param {Function} setter The function to set keys and values of the accumulator object.
* @param {Function} [initializer] The function to initialize the accumulator object.
* @returns {Function} Returns the new aggregator function.
*/
function createAggregator(setter, initializer) {
return function(collection, iteratee, thisArg) {
var result = initializer ? initializer() : {};
iteratee = getCallback(iteratee, thisArg, 3);
if (isArray(collection)) {
var index = -1,
length = collection.length;
while (++index < length) {
var value = collection[index];
setter(result, value, iteratee(value, index, collection), collection);
}
} else {
baseEach(collection, function(value, key, collection) {
setter(result, value, iteratee(value, key, collection), collection);
});
}
return result;
};
}
/**
* Creates a function that assigns properties of source object(s) to a given
* destination object.
*
* @private
* @param {Function} assigner The function to assign values.
* @returns {Function} Returns the new assigner function.
*/
function createAssigner(assigner) {
return function() {
var length = arguments.length,
object = arguments[0];
if (length < 2 || object == null) {
return object;
}
if (length > 3 && isIterateeCall(arguments[1], arguments[2], arguments[3])) {
length = 2;
}
// Juggle arguments.
if (length > 3 && typeof arguments[length - 2] == 'function') {
var customizer = bindCallback(arguments[--length - 1], arguments[length--], 5);
} else if (length > 2 && typeof arguments[length - 1] == 'function') {
customizer = arguments[--length];
}
var index = 0;
while (++index < length) {
var source = arguments[index];
if (source) {
assigner(object, source, customizer);
}
}
return object;
};
}
/**
* Creates a function that wraps `func` and invokes it with the `this`
* binding of `thisArg`.
*
* @private
* @param {Function} func The function to bind.
* @param {*} [thisArg] The `this` binding of `func`.
* @returns {Function} Returns the new bound function.
*/
function createBindWrapper(func, thisArg) {
var Ctor = createCtorWrapper(func);
function wrapper() {
return (this instanceof wrapper ? Ctor : func).apply(thisArg, arguments);
}
return wrapper;
}
/**
* Creates a `Set` cache object to optimize linear searches of large arrays.
*
* @private
* @param {Array} [values] The values to cache.
* @returns {null|Object} Returns the new cache object if `Set` is supported, else `null`.
*/
var createCache = !(nativeCreate && Set) ? constant(null) : function(values) {
return new SetCache(values);
};
/**
* Creates a function that produces compound words out of the words in a
* given string.
*
* @private
* @param {Function} callback The function to combine each word.
* @returns {Function} Returns the new compounder function.
*/
function createCompounder(callback) {
return function(string) {
var index = -1,
array = words(deburr(string)),
length = array.length,
result = '';
while (++index < length) {
result = callback(result, array[index], index);
}
return result;
};
}
/**
* Creates a function that produces an instance of `Ctor` regardless of
* whether it was invoked as part of a `new` expression or by `call` or `apply`.
*
* @private
* @param {Function} Ctor The constructor to wrap.
* @returns {Function} Returns the new wrapped function.
*/
function createCtorWrapper(Ctor) {
return function() {
var thisBinding = baseCreate(Ctor.prototype),
result = Ctor.apply(thisBinding, arguments);
// Mimic the constructor's `return` behavior.
// See https://es5.github.io/#x13.2.2 for more details.
return isObject(result) ? result : thisBinding;
};
}
/**
* Creates a function that gets the extremum value of a collection.
*
* @private
* @param {Function} arrayFunc The function to get the extremum value from an array.
* @param {boolean} [isMin] Specify returning the minimum, instead of the maximum,
* extremum value.
* @returns {Function} Returns the new extremum function.
*/
function createExtremum(arrayFunc, isMin) {
return function(collection, iteratee, thisArg) {
if (thisArg && isIterateeCall(collection, iteratee, thisArg)) {
iteratee = null;
}
var func = getCallback(),
noIteratee = iteratee == null;
if (!(func === baseCallback && noIteratee)) {
noIteratee = false;
iteratee = func(iteratee, thisArg, 3);
}
if (noIteratee) {
var isArr = isArray(collection);
if (!isArr && isString(collection)) {
iteratee = charAtCallback;
} else {
return arrayFunc(isArr ? collection : toIterable(collection));
}
}
return extremumBy(collection, iteratee, isMin);
};
}
/**
* Creates a function that wraps `func` and invokes it with optional `this`
* binding of, partial application, and currying.
*
* @private
* @param {Function|string} func The function or method name to reference.
* @param {number} bitmask The bitmask of flags. See `createWrapper` for more details.
* @param {*} [thisArg] The `this` binding of `func`.
* @param {Array} [partials] The arguments to prepend to those provided to the new function.
* @param {Array} [holders] The `partials` placeholder indexes.
* @param {Array} [partialsRight] The arguments to append to those provided to the new function.
* @param {Array} [holdersRight] The `partialsRight` placeholder indexes.
* @param {Array} [argPos] The argument positions of the new function.
* @param {number} [ary] The arity cap of `func`.
* @param {number} [arity] The arity of `func`.
* @returns {Function} Returns the new wrapped function.
*/
function createHybridWrapper(func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity) {
var isAry = bitmask & ARY_FLAG,
isBind = bitmask & BIND_FLAG,
isBindKey = bitmask & BIND_KEY_FLAG,
isCurry = bitmask & CURRY_FLAG,
isCurryBound = bitmask & CURRY_BOUND_FLAG,
isCurryRight = bitmask & CURRY_RIGHT_FLAG;
var Ctor = !isBindKey && createCtorWrapper(func),
key = func;
function wrapper() {
// Avoid `arguments` object use disqualifying optimizations by
// converting it to an array before providing it to other functions.
var length = arguments.length,
index = length,
args = Array(length);
while (index--) {
args[index] = arguments[index];
}
if (partials) {
args = composeArgs(args, partials, holders);
}
if (partialsRight) {
args = composeArgsRight(args, partialsRight, holdersRight);
}
if (isCurry || isCurryRight) {
var placeholder = wrapper.placeholder,
argsHolders = replaceHolders(args, placeholder);
length -= argsHolders.length;
if (length < arity) {
var newArgPos = argPos ? arrayCopy(argPos) : null,
newArity = nativeMax(arity - length, 0),
newsHolders = isCurry ? argsHolders : null,
newHoldersRight = isCurry ? null : argsHolders,
newPartials = isCurry ? args : null,
newPartialsRight = isCurry ? null : args;
bitmask |= (isCurry ? PARTIAL_FLAG : PARTIAL_RIGHT_FLAG);
bitmask &= ~(isCurry ? PARTIAL_RIGHT_FLAG : PARTIAL_FLAG);
if (!isCurryBound) {
bitmask &= ~(BIND_FLAG | BIND_KEY_FLAG);
}
var result = createHybridWrapper(func, bitmask, thisArg, newPartials, newsHolders, newPartialsRight, newHoldersRight, newArgPos, ary, newArity);
result.placeholder = placeholder;
return result;
}
}
var thisBinding = isBind ? thisArg : this;
if (isBindKey) {
func = thisBinding[key];
}
if (argPos) {
args = reorder(args, argPos);
}
if (isAry && ary < args.length) {
args.length = ary;
}
return (this instanceof wrapper ? (Ctor || createCtorWrapper(func)) : func).apply(thisBinding, args);
}
return wrapper;
}
/**
* Creates the pad required for `string` based on the given padding length.
* The `chars` string may be truncated if the number of padding characters
* exceeds the padding length.
*
* @private
* @param {string} string The string to create padding for.
* @param {number} [length=0] The padding length.
* @param {string} [chars=' '] The string used as padding.
* @returns {string} Returns the pad for `string`.
*/
function createPad(string, length, chars) {
var strLength = string.length;
length = +length;
if (strLength >= length || !nativeIsFinite(length)) {
return '';
}
var padLength = length - strLength;
chars = chars == null ? ' ' : (chars + '');
return repeat(chars, ceil(padLength / chars.length)).slice(0, padLength);
}
/**
* Creates a function that wraps `func` and invokes it with the optional `this`
* binding of `thisArg` and the `partials` prepended to those provided to
* the wrapper.
*
* @private
* @param {Function} func The function to partially apply arguments to.
* @param {number} bitmask The bitmask of flags. See `createWrapper` for more details.
* @param {*} thisArg The `this` binding of `func`.
* @param {Array} partials The arguments to prepend to those provided to the new function.
* @returns {Function} Returns the new bound function.
*/
function createPartialWrapper(func, bitmask, thisArg, partials) {
var isBind = bitmask & BIND_FLAG,
Ctor = createCtorWrapper(func);
function wrapper() {
// Avoid `arguments` object use disqualifying optimizations by
// converting it to an array before providing it `func`.
var argsIndex = -1,
argsLength = arguments.length,
leftIndex = -1,
leftLength = partials.length,
args = Array(argsLength + leftLength);
while (++leftIndex < leftLength) {
args[leftIndex] = partials[leftIndex];
}
while (argsLength--) {
args[leftIndex++] = arguments[++argsIndex];
}
return (this instanceof wrapper ? Ctor : func).apply(isBind ? thisArg : this, args);
}
return wrapper;
}
/**
* Creates a function that either curries or invokes `func` with optional
* `this` binding and partially applied arguments.
*
* @private
* @param {Function|string} func The function or method name to reference.
* @param {number} bitmask The bitmask of flags.
* The bitmask may be composed of the following flags:
* 1 - `_.bind`
* 2 - `_.bindKey`
* 4 - `_.curry` or `_.curryRight` of a bound function
* 8 - `_.curry`
* 16 - `_.curryRight`
* 32 - `_.partial`
* 64 - `_.partialRight`
* 128 - `_.rearg`
* 256 - `_.ary`
* @param {*} [thisArg] The `this` binding of `func`.
* @param {Array} [partials] The arguments to be partially applied.
* @param {Array} [holders] The `partials` placeholder indexes.
* @param {Array} [argPos] The argument positions of the new function.
* @param {number} [ary] The arity cap of `func`.
* @param {number} [arity] The arity of `func`.
* @returns {Function} Returns the new wrapped function.
*/
function createWrapper(func, bitmask, thisArg, partials, holders, argPos, ary, arity) {
var isBindKey = bitmask & BIND_KEY_FLAG;
if (!isBindKey && typeof func != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
var length = partials ? partials.length : 0;
if (!length) {
bitmask &= ~(PARTIAL_FLAG | PARTIAL_RIGHT_FLAG);
partials = holders = null;
}
length -= (holders ? holders.length : 0);
if (bitmask & PARTIAL_RIGHT_FLAG) {
var partialsRight = partials,
holdersRight = holders;
partials = holders = null;
}
var data = !isBindKey && getData(func),
newData = [func, bitmask, thisArg, partials, holders, partialsRight, holdersRight, argPos, ary, arity];
if (data && data !== true) {
mergeData(newData, data);
bitmask = newData[1];
arity = newData[9];
}
newData[9] = arity == null
? (isBindKey ? 0 : func.length)
: (nativeMax(arity - length, 0) || 0);
if (bitmask == BIND_FLAG) {
var result = createBindWrapper(newData[0], newData[2]);
} else if ((bitmask == PARTIAL_FLAG || bitmask == (BIND_FLAG | PARTIAL_FLAG)) && !newData[4].length) {
result = createPartialWrapper.apply(undefined, newData);
} else {
result = createHybridWrapper.apply(undefined, newData);
}
var setter = data ? baseSetData : setData;
return setter(result, newData);
}
/**
* A specialized version of `baseIsEqualDeep` for arrays with support for
* partial deep comparisons.
*
* @private
* @param {Array} array The array to compare.
* @param {Array} other The other array to compare.
* @param {Function} equalFunc The function to determine equivalents of values.
* @param {Function} [customizer] The function to customize comparing arrays.
* @param {boolean} [isWhere] Specify performing partial comparisons.
* @param {Array} [stackA] Tracks traversed `value` objects.
* @param {Array} [stackB] Tracks traversed `other` objects.
* @returns {boolean} Returns `true` if the arrays are equivalent, else `false`.
*/
function equalArrays(array, other, equalFunc, customizer, isWhere, stackA, stackB) {
var index = -1,
arrLength = array.length,
othLength = other.length,
result = true;
if (arrLength != othLength && !(isWhere && othLength > arrLength)) {
return false;
}
// Deep compare the contents, ignoring non-numeric properties.
while (result && ++index < arrLength) {
var arrValue = array[index],
othValue = other[index];
result = undefined;
if (customizer) {
result = isWhere
? customizer(othValue, arrValue, index)
: customizer(arrValue, othValue, index);
}
if (typeof result == 'undefined') {
// Recursively compare arrays (susceptible to call stack limits).
if (isWhere) {
var othIndex = othLength;
while (othIndex--) {
othValue = other[othIndex];
result = (arrValue && arrValue === othValue) || equalFunc(arrValue, othValue, customizer, isWhere, stackA, stackB);
if (result) {
break;
}
}
} else {
result = (arrValue && arrValue === othValue) || equalFunc(arrValue, othValue, customizer, isWhere, stackA, stackB);
}
}
}
return !!result;
}
/**
* A specialized version of `baseIsEqualDeep` for comparing objects of
* the same `toStringTag`.
*
* **Note:** This function only supports comparing values with tags of
* `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
*
* @private
* @param {Object} value The object to compare.
* @param {Object} other The other object to compare.
* @param {string} tag The `toStringTag` of the objects to compare.
* @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
*/
function equalByTag(object, other, tag) {
switch (tag) {
case boolTag:
case dateTag:
// Coerce dates and booleans to numbers, dates to milliseconds and booleans
// to `1` or `0` treating invalid dates coerced to `NaN` as not equal.
return +object == +other;
case errorTag:
return object.name == other.name && object.message == other.message;
case numberTag:
// Treat `NaN` vs. `NaN` as equal.
return (object != +object)
? other != +other
// But, treat `-0` vs. `+0` as not equal.
: (object == 0 ? ((1 / object) == (1 / other)) : object == +other);
case regexpTag:
case stringTag:
// Coerce regexes to strings and treat strings primitives and string
// objects as equal. See https://es5.github.io/#x15.10.6.4 for more details.
return object == (other + '');
}
return false;
}
/**
* A specialized version of `baseIsEqualDeep` for objects with support for
* partial deep comparisons.
*
* @private
* @param {Object} object The object to compare.
* @param {Object} other The other object to compare.
* @param {Function} equalFunc The function to determine equivalents of values.
* @param {Function} [customizer] The function to customize comparing values.
* @param {boolean} [isWhere] Specify performing partial comparisons.
* @param {Array} [stackA] Tracks traversed `value` objects.
* @param {Array} [stackB] Tracks traversed `other` objects.
* @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
*/
function equalObjects(object, other, equalFunc, customizer, isWhere, stackA, stackB) {
var objProps = keys(object),
objLength = objProps.length,
othProps = keys(other),
othLength = othProps.length;
if (objLength != othLength && !isWhere) {
return false;
}
var hasCtor,
index = -1;
while (++index < objLength) {
var key = objProps[index],
result = hasOwnProperty.call(other, key);
if (result) {
var objValue = object[key],
othValue = other[key];
result = undefined;
if (customizer) {
result = isWhere
? customizer(othValue, objValue, key)
: customizer(objValue, othValue, key);
}
if (typeof result == 'undefined') {
// Recursively compare objects (susceptible to call stack limits).
result = (objValue && objValue === othValue) || equalFunc(objValue, othValue, customizer, isWhere, stackA, stackB);
}
}
if (!result) {
return false;
}
hasCtor || (hasCtor = key == 'constructor');
}
if (!hasCtor) {
var objCtor = object.constructor,
othCtor = other.constructor;
// Non `Object` object instances with different constructors are not equal.
if (objCtor != othCtor && ('constructor' in object && 'constructor' in other) &&
!(typeof objCtor == 'function' && objCtor instanceof objCtor && typeof othCtor == 'function' && othCtor instanceof othCtor)) {
return false;
}
}
return true;
}
/**
* Gets the extremum value of `collection` invoking `iteratee` for each value
* in `collection` to generate the criterion by which the value is ranked.
* The `iteratee` is invoked with three arguments; (value, index, collection).
*
* @private
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} iteratee The function invoked per iteration.
* @param {boolean} [isMin] Specify returning the minimum, instead of the
* maximum, extremum value.
* @returns {*} Returns the extremum value.
*/
function extremumBy(collection, iteratee, isMin) {
var exValue = isMin ? POSITIVE_INFINITY : NEGATIVE_INFINITY,
computed = exValue,
result = computed;
baseEach(collection, function(value, index, collection) {
var current = iteratee(value, index, collection);
if ((isMin ? current < computed : current > computed) || (current === exValue && current === result)) {
computed = current;
result = value;
}
});
return result;
}
/**
* Gets the appropriate "callback" function. If the `_.callback` method is
* customized this function returns the custom method, otherwise it returns
* the `baseCallback` function. If arguments are provided the chosen function
* is invoked with them and its result is returned.
*
* @private
* @returns {Function} Returns the chosen function or its result.
*/
function getCallback(func, thisArg, argCount) {
var result = lodash.callback || callback;
result = result === callback ? baseCallback : result;
return argCount ? result(func, thisArg, argCount) : result;
}
/**
* Gets metadata for `func`.
*
* @private
* @param {Function} func The function to query.
* @returns {*} Returns the metadata for `func`.
*/
var getData = !metaMap ? noop : function(func) {
return metaMap.get(func);
};
/**
* Gets the appropriate "indexOf" function. If the `_.indexOf` method is
* customized this function returns the custom method, otherwise it returns
* the `baseIndexOf` function. If arguments are provided the chosen function
* is invoked with them and its result is returned.
*
* @private
* @returns {Function|number} Returns the chosen function or its result.
*/
function getIndexOf(collection, target, fromIndex) {
var result = lodash.indexOf || indexOf;
result = result === indexOf ? baseIndexOf : result;
return collection ? result(collection, target, fromIndex) : result;
}
/**
* Gets the view, applying any `transforms` to the `start` and `end` positions.
*
* @private
* @param {number} start The start of the view.
* @param {number} end The end of the view.
* @param {Array} [transforms] The transformations to apply to the view.
* @returns {Object} Returns an object containing the `start` and `end`
* positions of the view.
*/
function getView(start, end, transforms) {
var index = -1,
length = transforms ? transforms.length : 0;
while (++index < length) {
var data = transforms[index],
size = data.size;
switch (data.type) {
case 'drop': start += size; break;
case 'dropRight': end -= size; break;
case 'take': end = nativeMin(end, start + size); break;
case 'takeRight': start = nativeMax(start, end - size); break;
}
}
return { 'start': start, 'end': end };
}
/**
* Initializes an array clone.
*
* @private
* @param {Array} array The array to clone.
* @returns {Array} Returns the initialized clone.
*/
function initCloneArray(array) {
var length = array.length,
result = new array.constructor(length);
// Add array properties assigned by `RegExp#exec`.
if (length && typeof array[0] == 'string' && hasOwnProperty.call(array, 'index')) {
result.index = array.index;
result.input = array.input;
}
return result;
}
/**
* Initializes an object clone.
*
* @private
* @param {Object} object The object to clone.
* @returns {Object} Returns the initialized clone.
*/
function initCloneObject(object) {
var Ctor = object.constructor;
if (!(typeof Ctor == 'function' && Ctor instanceof Ctor)) {
Ctor = Object;
}
return new Ctor;
}
/**
* Initializes an object clone based on its `toStringTag`.
*
* **Note:** This function only supports cloning values with tags of
* `Boolean`, `Date`, `Error`, `Number`, `RegExp`, or `String`.
*
*
* @private
* @param {Object} object The object to clone.
* @param {string} tag The `toStringTag` of the object to clone.
* @param {boolean} [isDeep] Specify a deep clone.
* @returns {Object} Returns the initialized clone.
*/
function initCloneByTag(object, tag, isDeep) {
var Ctor = object.constructor;
switch (tag) {
case arrayBufferTag:
return bufferClone(object);
case boolTag:
case dateTag:
return new Ctor(+object);
case float32Tag: case float64Tag:
case int8Tag: case int16Tag: case int32Tag:
case uint8Tag: case uint8ClampedTag: case uint16Tag: case uint32Tag:
var buffer = object.buffer;
return new Ctor(isDeep ? bufferClone(buffer) : buffer, object.byteOffset, object.length);
case numberTag:
case stringTag:
return new Ctor(object);
case regexpTag:
var result = new Ctor(object.source, reFlags.exec(object));
result.lastIndex = object.lastIndex;
}
return result;
}
/**
* Checks if `func` is eligible for `this` binding.
*
* @private
* @param {Function} func The function to check.
* @returns {boolean} Returns `true` if `func` is eligible, else `false`.
*/
function isBindable(func) {
var support = lodash.support,
result = !(support.funcNames ? func.name : support.funcDecomp);
if (!result) {
var source = fnToString.call(func);
if (!support.funcNames) {
result = !reFuncName.test(source);
}
if (!result) {
// Check if `func` references the `this` keyword and store the result.
result = reThis.test(source) || isNative(func);
baseSetData(func, result);
}
}
return result;
}
/**
* Checks if `value` is a valid array-like index.
*
* @private
* @param {*} value The value to check.
* @param {number} [length=MAX_SAFE_INTEGER] The upper bounds of a valid index.
* @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
*/
function isIndex(value, length) {
value = +value;
length = length == null ? MAX_SAFE_INTEGER : length;
return value > -1 && value % 1 == 0 && value < length;
}
/**
* Checks if the provided arguments are from an iteratee call.
*
* @private
* @param {*} value The potential iteratee value argument.
* @param {*} index The potential iteratee index or key argument.
* @param {*} object The potential iteratee object argument.
* @returns {boolean} Returns `true` if the arguments are from an iteratee call, else `false`.
*/
function isIterateeCall(value, index, object) {
if (!isObject(object)) {
return false;
}
var type = typeof index;
if (type == 'number') {
var length = object.length,
prereq = isLength(length) && isIndex(index, length);
} else {
prereq = type == 'string' && index in object;
}
return prereq && object[index] === value;
}
/**
* Checks if `value` is a valid array-like length.
*
* **Note:** This function is based on ES `ToLength`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-tolength)
* for more details.
*
* @private
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a valid length, else `false`.
*/
function isLength(value) {
return typeof value == 'number' && value > -1 && value % 1 == 0 && value <= MAX_SAFE_INTEGER;
}
/**
* Checks if `value` is suitable for strict equality comparisons, i.e. `===`.
*
* @private
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` if suitable for strict
* equality comparisons, else `false`.
*/
function isStrictComparable(value) {
return value === value && (value === 0 ? ((1 / value) > 0) : !isObject(value));
}
/**
* Merges the function metadata of `source` into `data`.
*
* Merging metadata reduces the number of wrappers required to invoke a function.
* This is possible because methods like `_.bind`, `_.curry`, and `_.partial`
* may be applied regardless of execution order. Methods like `_.ary` and `_.rearg`
* augment function arguments, making the order in which they are executed important,
* preventing the merging of metadata. However, we make an exception for a safe
* common case where curried functions have `_.ary` and or `_.rearg` applied.
*
* @private
* @param {Array} data The destination metadata.
* @param {Array} source The source metadata.
* @returns {Array} Returns `data`.
*/
function mergeData(data, source) {
var bitmask = data[1],
srcBitmask = source[1],
newBitmask = bitmask | srcBitmask;
var arityFlags = ARY_FLAG | REARG_FLAG,
bindFlags = BIND_FLAG | BIND_KEY_FLAG,
comboFlags = arityFlags | bindFlags | CURRY_BOUND_FLAG | CURRY_RIGHT_FLAG;
var isAry = bitmask & ARY_FLAG && !(srcBitmask & ARY_FLAG),
isRearg = bitmask & REARG_FLAG && !(srcBitmask & REARG_FLAG),
argPos = (isRearg ? data : source)[7],
ary = (isAry ? data : source)[8];
var isCommon = !(bitmask >= REARG_FLAG && srcBitmask > bindFlags) &&
!(bitmask > bindFlags && srcBitmask >= REARG_FLAG);
var isCombo = (newBitmask >= arityFlags && newBitmask <= comboFlags) &&
(bitmask < REARG_FLAG || ((isRearg || isAry) && argPos.length <= ary));
// Exit early if metadata can't be merged.
if (!(isCommon || isCombo)) {
return data;
}
// Use source `thisArg` if available.
if (srcBitmask & BIND_FLAG) {
data[2] = source[2];
// Set when currying a bound function.
newBitmask |= (bitmask & BIND_FLAG) ? 0 : CURRY_BOUND_FLAG;
}
// Compose partial arguments.
var value = source[3];
if (value) {
var partials = data[3];
data[3] = partials ? composeArgs(partials, value, source[4]) : arrayCopy(value);
data[4] = partials ? replaceHolders(data[3], PLACEHOLDER) : arrayCopy(source[4]);
}
// Compose partial right arguments.
value = source[5];
if (value) {
partials = data[5];
data[5] = partials ? composeArgsRight(partials, value, source[6]) : arrayCopy(value);
data[6] = partials ? replaceHolders(data[5], PLACEHOLDER) : arrayCopy(source[6]);
}
// Use source `argPos` if available.
value = source[7];
if (value) {
data[7] = arrayCopy(value);
}
// Use source `ary` if it's smaller.
if (srcBitmask & ARY_FLAG) {
data[8] = data[8] == null ? source[8] : nativeMin(data[8], source[8]);
}
// Use source `arity` if one is not provided.
if (data[9] == null) {
data[9] = source[9];
}
// Use source `func` and merge bitmasks.
data[0] = source[0];
data[1] = newBitmask;
return data;
}
/**
* A specialized version of `_.pick` that picks `object` properties specified
* by the `props` array.
*
* @private
* @param {Object} object The source object.
* @param {string[]} props The property names to pick.
* @returns {Object} Returns the new object.
*/
function pickByArray(object, props) {
object = toObject(object);
var index = -1,
length = props.length,
result = {};
while (++index < length) {
var key = props[index];
if (key in object) {
result[key] = object[key];
}
}
return result;
}
/**
* A specialized version of `_.pick` that picks `object` properties `predicate`
* returns truthy for.
*
* @private
* @param {Object} object The source object.
* @param {Function} predicate The function invoked per iteration.
* @returns {Object} Returns the new object.
*/
function pickByCallback(object, predicate) {
var result = {};
baseForIn(object, function(value, key, object) {
if (predicate(value, key, object)) {
result[key] = value;
}
});
return result;
}
/**
* Reorder `array` according to the specified indexes where the element at
* the first index is assigned as the first element, the element at
* the second index is assigned as the second element, and so on.
*
* @private
* @param {Array} array The array to reorder.
* @param {Array} indexes The arranged array indexes.
* @returns {Array} Returns `array`.
*/
function reorder(array, indexes) {
var arrLength = array.length,
length = nativeMin(indexes.length, arrLength),
oldArray = arrayCopy(array);
while (length--) {
var index = indexes[length];
array[length] = isIndex(index, arrLength) ? oldArray[index] : undefined;
}
return array;
}
/**
* Sets metadata for `func`.
*
* **Note:** If this function becomes hot, i.e. is invoked a lot in a short
* period of time, it will trip its breaker and transition to an identity function
* to avoid garbage collection pauses in V8. See [V8 issue 2070](https://code.google.com/p/v8/issues/detail?id=2070)
* for more details.
*
* @private
* @param {Function} func The function to associate metadata with.
* @param {*} data The metadata.
* @returns {Function} Returns `func`.
*/
var setData = (function() {
var count = 0,
lastCalled = 0;
return function(key, value) {
var stamp = now(),
remaining = HOT_SPAN - (stamp - lastCalled);
lastCalled = stamp;
if (remaining > 0) {
if (++count >= HOT_COUNT) {
return key;
}
} else {
count = 0;
}
return baseSetData(key, value);
};
}());
/**
* A fallback implementation of `_.isPlainObject` which checks if `value`
* is an object created by the `Object` constructor or has a `[[Prototype]]`
* of `null`.
*
* @private
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
*/
function shimIsPlainObject(value) {
var Ctor,
support = lodash.support;
// Exit early for non `Object` objects.
if (!(isObjectLike(value) && objToString.call(value) == objectTag) ||
(!hasOwnProperty.call(value, 'constructor') &&
(Ctor = value.constructor, typeof Ctor == 'function' && !(Ctor instanceof Ctor)))) {
return false;
}
// IE < 9 iterates inherited properties before own properties. If the first
// iterated property is an object's own property then there are no inherited
// enumerable properties.
var result;
// In most environments an object's own properties are iterated before
// its inherited properties. If the last iterated property is an object's
// own property then there are no inherited enumerable properties.
baseForIn(value, function(subValue, key) {
result = key;
});
return typeof result == 'undefined' || hasOwnProperty.call(value, result);
}
/**
* A fallback implementation of `Object.keys` which creates an array of the
* own enumerable property names of `object`.
*
* @private
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property names.
*/
function shimKeys(object) {
var props = keysIn(object),
propsLength = props.length,
length = propsLength && object.length,
support = lodash.support;
var allowIndexes = length && isLength(length) &&
(isArray(object) || (support.nonEnumArgs && isArguments(object)));
var index = -1,
result = [];
while (++index < propsLength) {
var key = props[index];
if ((allowIndexes && isIndex(key, length)) || hasOwnProperty.call(object, key)) {
result.push(key);
}
}
return result;
}
/**
* Converts `value` to an array-like object if it is not one.
*
* @private
* @param {*} value The value to process.
* @returns {Array|Object} Returns the array-like object.
*/
function toIterable(value) {
if (value == null) {
return [];
}
if (!isLength(value.length)) {
return values(value);
}
return isObject(value) ? value : Object(value);
}
/**
* Converts `value` to an object if it is not one.
*
* @private
* @param {*} value The value to process.
* @returns {Object} Returns the object.
*/
function toObject(value) {
return isObject(value) ? value : Object(value);
}
/**
* Creates a clone of `wrapper`.
*
* @private
* @param {Object} wrapper The wrapper to clone.
* @returns {Object} Returns the cloned wrapper.
*/
function wrapperClone(wrapper) {
return wrapper instanceof LazyWrapper
? wrapper.clone()
: new LodashWrapper(wrapper.__wrapped__, wrapper.__chain__, arrayCopy(wrapper.__actions__));
}
/*------------------------------------------------------------------------*/
/**
* Creates an array of elements split into groups the length of `size`.
* If `collection` can't be split evenly, the final chunk will be the remaining
* elements.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to process.
* @param {number} [size=1] The length of each chunk.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the new array containing chunks.
* @example
*
* _.chunk(['a', 'b', 'c', 'd'], 2);
* // => [['a', 'b'], ['c', 'd']]
*
* _.chunk(['a', 'b', 'c', 'd'], 3);
* // => [['a', 'b', 'c'], ['d']]
*/
function chunk(array, size, guard) {
if (guard ? isIterateeCall(array, size, guard) : size == null) {
size = 1;
} else {
size = nativeMax(+size || 1, 1);
}
var index = 0,
length = array ? array.length : 0,
resIndex = -1,
result = Array(ceil(length / size));
while (index < length) {
result[++resIndex] = baseSlice(array, index, (index += size));
}
return result;
}
/**
* Creates an array with all falsey values removed. The values `false`, `null`,
* `0`, `""`, `undefined`, and `NaN` are falsey.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to compact.
* @returns {Array} Returns the new array of filtered values.
* @example
*
* _.compact([0, 1, false, 2, '', 3]);
* // => [1, 2, 3]
*/
function compact(array) {
var index = -1,
length = array ? array.length : 0,
resIndex = -1,
result = [];
while (++index < length) {
var value = array[index];
if (value) {
result[++resIndex] = value;
}
}
return result;
}
/**
* Creates an array excluding all values of the provided arrays using
* `SameValueZero` for equality comparisons.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to inspect.
* @param {...Array} [values] The arrays of values to exclude.
* @returns {Array} Returns the new array of filtered values.
* @example
*
* _.difference([1, 2, 3], [5, 2, 10]);
* // => [1, 3]
*/
function difference() {
var index = -1,
length = arguments.length;
while (++index < length) {
var value = arguments[index];
if (isArray(value) || isArguments(value)) {
break;
}
}
return baseDifference(value, baseFlatten(arguments, false, true, ++index));
}
/**
* Creates a slice of `array` with `n` elements dropped from the beginning.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {number} [n=1] The number of elements to drop.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.drop([1, 2, 3]);
* // => [2, 3]
*
* _.drop([1, 2, 3], 2);
* // => [3]
*
* _.drop([1, 2, 3], 5);
* // => []
*
* _.drop([1, 2, 3], 0);
* // => [1, 2, 3]
*/
function drop(array, n, guard) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
if (guard ? isIterateeCall(array, n, guard) : n == null) {
n = 1;
}
return baseSlice(array, n < 0 ? 0 : n);
}
/**
* Creates a slice of `array` with `n` elements dropped from the end.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {number} [n=1] The number of elements to drop.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.dropRight([1, 2, 3]);
* // => [1, 2]
*
* _.dropRight([1, 2, 3], 2);
* // => [1]
*
* _.dropRight([1, 2, 3], 5);
* // => []
*
* _.dropRight([1, 2, 3], 0);
* // => [1, 2, 3]
*/
function dropRight(array, n, guard) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
if (guard ? isIterateeCall(array, n, guard) : n == null) {
n = 1;
}
n = length - (+n || 0);
return baseSlice(array, 0, n < 0 ? 0 : n);
}
/**
* Creates a slice of `array` excluding elements dropped from the end.
* Elements are dropped until `predicate` returns falsey. The predicate is
* bound to `thisArg` and invoked with three arguments; (value, index, array).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that match the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per element.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.dropRightWhile([1, 2, 3], function(n) { return n > 1; });
* // => [1]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': true },
* { 'user': 'fred', 'age': 40, 'active': false },
* { 'user': 'pebbles', 'age': 1, 'active': false }
* ];
*
* // using the "_.matches" callback shorthand
* _.pluck(_.dropRightWhile(users, { 'age': 1, 'active': false }), 'user');
* // => ['barney', 'fred']
*
* // using the "_.matchesProperty" callback shorthand
* _.pluck(_.dropRightWhile(users, 'active', false), 'user');
* // => ['barney']
*
* // using the "_.property" callback shorthand
* _.pluck(_.dropRightWhile(users, 'active'), 'user');
* // => ['barney', 'fred', 'pebbles']
*/
function dropRightWhile(array, predicate, thisArg) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
predicate = getCallback(predicate, thisArg, 3);
while (length-- && predicate(array[length], length, array)) {}
return baseSlice(array, 0, length + 1);
}
/**
* Creates a slice of `array` excluding elements dropped from the beginning.
* Elements are dropped until `predicate` returns falsey. The predicate is
* bound to `thisArg` and invoked with three arguments; (value, index, array).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per element.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.dropWhile([1, 2, 3], function(n) { return n < 3; });
* // => [3]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': false },
* { 'user': 'pebbles', 'age': 1, 'active': true }
* ];
*
* // using the "_.matches" callback shorthand
* _.pluck(_.dropWhile(users, { 'age': 36, 'active': false }), 'user');
* // => ['fred', 'pebbles']
*
* // using the "_.matchesProperty" callback shorthand
* _.pluck(_.dropWhile(users, 'active', false), 'user');
* // => ['pebbles']
*
* // using the "_.property" callback shorthand
* _.pluck(_.dropWhile(users, 'active'), 'user');
* // => ['barney', 'fred', 'pebbles']
*/
function dropWhile(array, predicate, thisArg) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
var index = -1;
predicate = getCallback(predicate, thisArg, 3);
while (++index < length && predicate(array[index], index, array)) {}
return baseSlice(array, index);
}
/**
* Fills elements of `array` with `value` from `start` up to, but not
* including, `end`.
*
* **Note:** This method mutates `array`.
*
* @private
* @param {Array} array The array to fill.
* @param {*} value The value to fill `array` with.
* @param {number} [start=0] The start position.
* @param {number} [end=array.length] The end position.
* @returns {Array} Returns `array`.
*/
function fill(array, value, start, end) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
if (start && typeof start != 'number' && isIterateeCall(array, value, start)) {
start = 0;
end = length;
}
return baseFill(array, value, start, end);
}
/**
* This method is like `_.find` except that it returns the index of the first
* element `predicate` returns truthy for, instead of the element itself.
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to search.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {number} Returns the index of the found element, else `-1`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': true },
* { 'user': 'pebbles', 'age': 1, 'active': false }
* ];
*
* _.findIndex(users, function(chr) { return chr.age < 40; });
* // => 0
*
* // using the "_.matches" callback shorthand
* _.findIndex(users, { 'age': 40, 'active': true });
* // => 1
*
* // using the "_.matchesProperty" callback shorthand
* _.findIndex(users, 'age', 1);
* // => 2
*
* // using the "_.property" callback shorthand
* _.findIndex(users, 'active');
* // => 1
*/
function findIndex(array, predicate, thisArg) {
var index = -1,
length = array ? array.length : 0;
predicate = getCallback(predicate, thisArg, 3);
while (++index < length) {
if (predicate(array[index], index, array)) {
return index;
}
}
return -1;
}
/**
* This method is like `_.findIndex` except that it iterates over elements
* of `collection` from right to left.
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to search.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {number} Returns the index of the found element, else `-1`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': true },
* { 'user': 'fred', 'age': 40, 'active': false },
* { 'user': 'pebbles', 'age': 1, 'active': false }
* ];
*
* _.findLastIndex(users, function(chr) { return chr.age < 40; });
* // => 2
*
* // using the "_.matches" callback shorthand
* _.findLastIndex(users, { 'age': 36, 'active': true });
* // => 0
*
* // using the "_.matchesProperty" callback shorthand
* _.findLastIndex(users, 'age', 40);
* // => 1
*
* // using the "_.property" callback shorthand
* _.findLastIndex(users, 'active');
* // => 0
*/
function findLastIndex(array, predicate, thisArg) {
var length = array ? array.length : 0;
predicate = getCallback(predicate, thisArg, 3);
while (length--) {
if (predicate(array[length], length, array)) {
return length;
}
}
return -1;
}
/**
* Gets the first element of `array`.
*
* @static
* @memberOf _
* @alias head
* @category Array
* @param {Array} array The array to query.
* @returns {*} Returns the first element of `array`.
* @example
*
* _.first([1, 2, 3]);
* // => 1
*
* _.first([]);
* // => undefined
*/
function first(array) {
return array ? array[0] : undefined;
}
/**
* Flattens a nested array. If `isDeep` is `true` the array is recursively
* flattened, otherwise it is only flattened a single level.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to flatten.
* @param {boolean} [isDeep] Specify a deep flatten.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the new flattened array.
* @example
*
* _.flatten([1, [2], [3, [[4]]]]);
* // => [1, 2, 3, [[4]]];
*
* // using `isDeep`
* _.flatten([1, [2], [3, [[4]]]], true);
* // => [1, 2, 3, 4];
*/
function flatten(array, isDeep, guard) {
var length = array ? array.length : 0;
if (guard && isIterateeCall(array, isDeep, guard)) {
isDeep = false;
}
return length ? baseFlatten(array, isDeep) : [];
}
/**
* Recursively flattens a nested array.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to recursively flatten.
* @returns {Array} Returns the new flattened array.
* @example
*
* _.flattenDeep([1, [2], [3, [[4]]]]);
* // => [1, 2, 3, 4];
*/
function flattenDeep(array) {
var length = array ? array.length : 0;
return length ? baseFlatten(array, true) : [];
}
/**
* Gets the index at which the first occurrence of `value` is found in `array`
* using `SameValueZero` for equality comparisons. If `fromIndex` is negative,
* it is used as the offset from the end of `array`. If `array` is sorted
* providing `true` for `fromIndex` performs a faster binary search.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to search.
* @param {*} value The value to search for.
* @param {boolean|number} [fromIndex=0] The index to search from or `true`
* to perform a binary search on a sorted array.
* @returns {number} Returns the index of the matched value, else `-1`.
* @example
*
* _.indexOf([1, 2, 3, 1, 2, 3], 2);
* // => 1
*
* // using `fromIndex`
* _.indexOf([1, 2, 3, 1, 2, 3], 2, 3);
* // => 4
*
* // performing a binary search
* _.indexOf([4, 4, 5, 5, 6, 6], 5, true);
* // => 2
*/
function indexOf(array, value, fromIndex) {
var length = array ? array.length : 0;
if (!length) {
return -1;
}
if (typeof fromIndex == 'number') {
fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : (fromIndex || 0);
} else if (fromIndex) {
var index = binaryIndex(array, value),
other = array[index];
return (value === value ? value === other : other !== other) ? index : -1;
}
return baseIndexOf(array, value, fromIndex);
}
/**
* Gets all but the last element of `array`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.initial([1, 2, 3]);
* // => [1, 2]
*/
function initial(array) {
return dropRight(array, 1);
}
/**
* Creates an array of unique values in all provided arrays using `SameValueZero`
* for equality comparisons.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to inspect.
* @returns {Array} Returns the new array of shared values.
* @example
*
* _.intersection([1, 2, 3], [5, 2, 1, 4], [2, 1]);
* // => [1, 2]
*/
function intersection() {
var args = [],
argsIndex = -1,
argsLength = arguments.length,
caches = [],
indexOf = getIndexOf(),
isCommon = indexOf == baseIndexOf;
while (++argsIndex < argsLength) {
var value = arguments[argsIndex];
if (isArray(value) || isArguments(value)) {
args.push(value);
caches.push(isCommon && value.length >= 120 && createCache(argsIndex && value));
}
}
argsLength = args.length;
var array = args[0],
index = -1,
length = array ? array.length : 0,
result = [],
seen = caches[0];
outer:
while (++index < length) {
value = array[index];
if ((seen ? cacheIndexOf(seen, value) : indexOf(result, value)) < 0) {
argsIndex = argsLength;
while (--argsIndex) {
var cache = caches[argsIndex];
if ((cache ? cacheIndexOf(cache, value) : indexOf(args[argsIndex], value)) < 0) {
continue outer;
}
}
if (seen) {
seen.push(value);
}
result.push(value);
}
}
return result;
}
/**
* Gets the last element of `array`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @returns {*} Returns the last element of `array`.
* @example
*
* _.last([1, 2, 3]);
* // => 3
*/
function last(array) {
var length = array ? array.length : 0;
return length ? array[length - 1] : undefined;
}
/**
* This method is like `_.indexOf` except that it iterates over elements of
* `array` from right to left.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to search.
* @param {*} value The value to search for.
* @param {boolean|number} [fromIndex=array.length-1] The index to search from
* or `true` to perform a binary search on a sorted array.
* @returns {number} Returns the index of the matched value, else `-1`.
* @example
*
* _.lastIndexOf([1, 2, 3, 1, 2, 3], 2);
* // => 4
*
* // using `fromIndex`
* _.lastIndexOf([1, 2, 3, 1, 2, 3], 2, 3);
* // => 1
*
* // performing a binary search
* _.lastIndexOf([4, 4, 5, 5, 6, 6], 5, true);
* // => 3
*/
function lastIndexOf(array, value, fromIndex) {
var length = array ? array.length : 0;
if (!length) {
return -1;
}
var index = length;
if (typeof fromIndex == 'number') {
index = (fromIndex < 0 ? nativeMax(length + fromIndex, 0) : nativeMin(fromIndex || 0, length - 1)) + 1;
} else if (fromIndex) {
index = binaryIndex(array, value, true) - 1;
var other = array[index];
return (value === value ? value === other : other !== other) ? index : -1;
}
if (value !== value) {
return indexOfNaN(array, index, true);
}
while (index--) {
if (array[index] === value) {
return index;
}
}
return -1;
}
/**
* Removes all provided values from `array` using `SameValueZero` for equality
* comparisons.
*
* **Notes:**
* - Unlike `_.without`, this method mutates `array`.
* - `SameValueZero` comparisons are like strict equality comparisons, e.g. `===`,
* except that `NaN` matches `NaN`. See the [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to modify.
* @param {...*} [values] The values to remove.
* @returns {Array} Returns `array`.
* @example
*
* var array = [1, 2, 3, 1, 2, 3];
* _.pull(array, 2, 3);
* console.log(array);
* // => [1, 1]
*/
function pull() {
var array = arguments[0];
if (!(array && array.length)) {
return array;
}
var index = 0,
indexOf = getIndexOf(),
length = arguments.length;
while (++index < length) {
var fromIndex = 0,
value = arguments[index];
while ((fromIndex = indexOf(array, value, fromIndex)) > -1) {
splice.call(array, fromIndex, 1);
}
}
return array;
}
/**
* Removes elements from `array` corresponding to the given indexes and returns
* an array of the removed elements. Indexes may be specified as an array of
* indexes or as individual arguments.
*
* **Note:** Unlike `_.at`, this method mutates `array`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to modify.
* @param {...(number|number[])} [indexes] The indexes of elements to remove,
* specified as individual indexes or arrays of indexes.
* @returns {Array} Returns the new array of removed elements.
* @example
*
* var array = [5, 10, 15, 20];
* var evens = _.pullAt(array, [1, 3]);
*
* console.log(array);
* // => [5, 15]
*
* console.log(evens);
* // => [10, 20]
*/
function pullAt(array) {
return basePullAt(array || [], baseFlatten(arguments, false, false, 1));
}
/**
* Removes all elements from `array` that `predicate` returns truthy for
* and returns an array of the removed elements. The predicate is bound to
* `thisArg` and invoked with three arguments; (value, index, array).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* **Note:** Unlike `_.filter`, this method mutates `array`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to modify.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the new array of removed elements.
* @example
*
* var array = [1, 2, 3, 4];
* var evens = _.remove(array, function(n) { return n % 2 == 0; });
*
* console.log(array);
* // => [1, 3]
*
* console.log(evens);
* // => [2, 4]
*/
function remove(array, predicate, thisArg) {
var index = -1,
length = array ? array.length : 0,
result = [];
predicate = getCallback(predicate, thisArg, 3);
while (++index < length) {
var value = array[index];
if (predicate(value, index, array)) {
result.push(value);
splice.call(array, index--, 1);
length--;
}
}
return result;
}
/**
* Gets all but the first element of `array`.
*
* @static
* @memberOf _
* @alias tail
* @category Array
* @param {Array} array The array to query.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.rest([1, 2, 3]);
* // => [2, 3]
*/
function rest(array) {
return drop(array, 1);
}
/**
* Creates a slice of `array` from `start` up to, but not including, `end`.
*
* **Note:** This function is used instead of `Array#slice` to support node
* lists in IE < 9 and to ensure dense arrays are returned.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to slice.
* @param {number} [start=0] The start position.
* @param {number} [end=array.length] The end position.
* @returns {Array} Returns the slice of `array`.
*/
function slice(array, start, end) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
if (end && typeof end != 'number' && isIterateeCall(array, start, end)) {
start = 0;
end = length;
}
return baseSlice(array, start, end);
}
/**
* Uses a binary search to determine the lowest index at which `value` should
* be inserted into `array` in order to maintain its sort order. If an iteratee
* function is provided it is invoked for `value` and each element of `array`
* to compute their sort ranking. The iteratee is bound to `thisArg` and
* invoked with one argument; (value).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The sorted array to inspect.
* @param {*} value The value to evaluate.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {number} Returns the index at which `value` should be inserted
* into `array`.
* @example
*
* _.sortedIndex([30, 50], 40);
* // => 1
*
* _.sortedIndex([4, 4, 5, 5, 6, 6], 5);
* // => 2
*
* var dict = { 'data': { 'thirty': 30, 'forty': 40, 'fifty': 50 } };
*
* // using an iteratee function
* _.sortedIndex(['thirty', 'fifty'], 'forty', function(word) {
* return this.data[word];
* }, dict);
* // => 1
*
* // using the "_.property" callback shorthand
* _.sortedIndex([{ 'x': 30 }, { 'x': 50 }], { 'x': 40 }, 'x');
* // => 1
*/
function sortedIndex(array, value, iteratee, thisArg) {
var func = getCallback(iteratee);
return (func === baseCallback && iteratee == null)
? binaryIndex(array, value)
: binaryIndexBy(array, value, func(iteratee, thisArg, 1));
}
/**
* This method is like `_.sortedIndex` except that it returns the highest
* index at which `value` should be inserted into `array` in order to
* maintain its sort order.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The sorted array to inspect.
* @param {*} value The value to evaluate.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {number} Returns the index at which `value` should be inserted
* into `array`.
* @example
*
* _.sortedLastIndex([4, 4, 5, 5, 6, 6], 5);
* // => 4
*/
function sortedLastIndex(array, value, iteratee, thisArg) {
var func = getCallback(iteratee);
return (func === baseCallback && iteratee == null)
? binaryIndex(array, value, true)
: binaryIndexBy(array, value, func(iteratee, thisArg, 1), true);
}
/**
* Creates a slice of `array` with `n` elements taken from the beginning.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {number} [n=1] The number of elements to take.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.take([1, 2, 3]);
* // => [1]
*
* _.take([1, 2, 3], 2);
* // => [1, 2]
*
* _.take([1, 2, 3], 5);
* // => [1, 2, 3]
*
* _.take([1, 2, 3], 0);
* // => []
*/
function take(array, n, guard) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
if (guard ? isIterateeCall(array, n, guard) : n == null) {
n = 1;
}
return baseSlice(array, 0, n < 0 ? 0 : n);
}
/**
* Creates a slice of `array` with `n` elements taken from the end.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {number} [n=1] The number of elements to take.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.takeRight([1, 2, 3]);
* // => [3]
*
* _.takeRight([1, 2, 3], 2);
* // => [2, 3]
*
* _.takeRight([1, 2, 3], 5);
* // => [1, 2, 3]
*
* _.takeRight([1, 2, 3], 0);
* // => []
*/
function takeRight(array, n, guard) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
if (guard ? isIterateeCall(array, n, guard) : n == null) {
n = 1;
}
n = length - (+n || 0);
return baseSlice(array, n < 0 ? 0 : n);
}
/**
* Creates a slice of `array` with elements taken from the end. Elements are
* taken until `predicate` returns falsey. The predicate is bound to `thisArg`
* and invoked with three arguments; (value, index, array).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per element.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.takeRightWhile([1, 2, 3], function(n) { return n > 1; });
* // => [2, 3]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': true },
* { 'user': 'fred', 'age': 40, 'active': false },
* { 'user': 'pebbles', 'age': 1, 'active': false }
* ];
*
* // using the "_.matches" callback shorthand
* _.pluck(_.takeRightWhile(users, { 'age': 1, 'active': true }), 'user');
* // => ['pebbles']
*
* // using the "_.matchesProperty" callback shorthand
* _.pluck(_.takeRightWhile(users, 'active', false), 'user');
* // => ['fred', 'pebbles']
*
* // using the "_.property" callback shorthand
* _.pluck(_.takeRightWhile(users, 'active'), 'user');
* // => []
*/
function takeRightWhile(array, predicate, thisArg) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
predicate = getCallback(predicate, thisArg, 3);
while (length-- && predicate(array[length], length, array)) {}
return baseSlice(array, length + 1);
}
/**
* Creates a slice of `array` with elements taken from the beginning. Elements
* are taken until `predicate` returns falsey. The predicate is bound to
* `thisArg` and invoked with three arguments; (value, index, array).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to query.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per element.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the slice of `array`.
* @example
*
* _.takeWhile([1, 2, 3], function(n) { return n < 3; });
* // => [1, 2]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': false },
* { 'user': 'pebbles', 'age': 1, 'active': true }
* ];
*
* // using the "_.matches" callback shorthand
* _.pluck(_.takeWhile(users, { 'age': 36, 'active': true }), 'user');
* // => ['barney']
*
* // using the "_.matchesProperty" callback shorthand
* _.pluck(_.takeWhile(users, 'active', false), 'user');
* // => ['barney', 'fred']
*
* // using the "_.property" callback shorthand
* _.pluck(_.takeWhile(users, 'active'), 'user');
* // => []
*/
function takeWhile(array, predicate, thisArg) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
var index = -1;
predicate = getCallback(predicate, thisArg, 3);
while (++index < length && predicate(array[index], index, array)) {}
return baseSlice(array, 0, index);
}
/**
* Creates an array of unique values, in order, of the provided arrays using
* `SameValueZero` for equality comparisons.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to inspect.
* @returns {Array} Returns the new array of combined values.
* @example
*
* _.union([1, 2, 3], [5, 2, 1, 4], [2, 1]);
* // => [1, 2, 3, 5, 4]
*/
function union() {
return baseUniq(baseFlatten(arguments, false, true));
}
/**
* Creates a duplicate-value-free version of an array using `SameValueZero`
* for equality comparisons. Providing `true` for `isSorted` performs a faster
* search algorithm for sorted arrays. If an iteratee function is provided it
* is invoked for each value in the array to generate the criterion by which
* uniqueness is computed. The `iteratee` is bound to `thisArg` and invoked
* with three arguments; (value, index, array).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @alias unique
* @category Array
* @param {Array} array The array to inspect.
* @param {boolean} [isSorted] Specify the array is sorted.
* @param {Function|Object|string} [iteratee] The function invoked per iteration.
* If a property name or object is provided it is used to create a "_.property"
* or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array} Returns the new duplicate-value-free array.
* @example
*
* _.uniq([1, 2, 1]);
* // => [1, 2]
*
* // using `isSorted`
* _.uniq([1, 1, 2], true);
* // => [1, 2]
*
* // using an iteratee function
* _.uniq([1, 2.5, 1.5, 2], function(n) { return this.floor(n); }, Math);
* // => [1, 2.5]
*
* // using the "_.property" callback shorthand
* _.uniq([{ 'x': 1 }, { 'x': 2 }, { 'x': 1 }], 'x');
* // => [{ 'x': 1 }, { 'x': 2 }]
*/
function uniq(array, isSorted, iteratee, thisArg) {
var length = array ? array.length : 0;
if (!length) {
return [];
}
// Juggle arguments.
if (typeof isSorted != 'boolean' && isSorted != null) {
thisArg = iteratee;
iteratee = isIterateeCall(array, isSorted, thisArg) ? null : isSorted;
isSorted = false;
}
var func = getCallback();
if (!(func === baseCallback && iteratee == null)) {
iteratee = func(iteratee, thisArg, 3);
}
return (isSorted && getIndexOf() == baseIndexOf)
? sortedUniq(array, iteratee)
: baseUniq(array, iteratee);
}
/**
* This method is like `_.zip` except that it accepts an array of grouped
* elements and creates an array regrouping the elements to their pre-`_.zip`
* configuration.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array of grouped elements to process.
* @returns {Array} Returns the new array of regrouped elements.
* @example
*
* var zipped = _.zip(['fred', 'barney'], [30, 40], [true, false]);
* // => [['fred', 30, true], ['barney', 40, false]]
*
* _.unzip(zipped);
* // => [['fred', 'barney'], [30, 40], [true, false]]
*/
function unzip(array) {
var index = -1,
length = (array && array.length && arrayMax(arrayMap(array, getLength))) >>> 0,
result = Array(length);
while (++index < length) {
result[index] = arrayMap(array, baseProperty(index));
}
return result;
}
/**
* Creates an array excluding all provided values using `SameValueZero` for
* equality comparisons.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @category Array
* @param {Array} array The array to filter.
* @param {...*} [values] The values to exclude.
* @returns {Array} Returns the new array of filtered values.
* @example
*
* _.without([1, 2, 1, 0, 3, 1, 4], 0, 1);
* // => [2, 3, 4]
*/
function without(array) {
return baseDifference(array, baseSlice(arguments, 1));
}
/**
* Creates an array that is the symmetric difference of the provided arrays.
* See [Wikipedia](https://en.wikipedia.org/wiki/Symmetric_difference) for
* more details.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to inspect.
* @returns {Array} Returns the new array of values.
* @example
*
* _.xor([1, 2, 3], [5, 2, 1, 4]);
* // => [3, 5, 4]
*
* _.xor([1, 2, 5], [2, 3, 5], [3, 4, 5]);
* // => [1, 4, 5]
*/
function xor() {
var index = -1,
length = arguments.length;
while (++index < length) {
var array = arguments[index];
if (isArray(array) || isArguments(array)) {
var result = result
? baseDifference(result, array).concat(baseDifference(array, result))
: array;
}
}
return result ? baseUniq(result) : [];
}
/**
* Creates an array of grouped elements, the first of which contains the first
* elements of the given arrays, the second of which contains the second elements
* of the given arrays, and so on.
*
* @static
* @memberOf _
* @category Array
* @param {...Array} [arrays] The arrays to process.
* @returns {Array} Returns the new array of grouped elements.
* @example
*
* _.zip(['fred', 'barney'], [30, 40], [true, false]);
* // => [['fred', 30, true], ['barney', 40, false]]
*/
function zip() {
var length = arguments.length,
array = Array(length);
while (length--) {
array[length] = arguments[length];
}
return unzip(array);
}
/**
* Creates an object composed from arrays of property names and values. Provide
* either a single two dimensional array, e.g. `[[key1, value1], [key2, value2]]`
* or two arrays, one of property names and one of corresponding values.
*
* @static
* @memberOf _
* @alias object
* @category Array
* @param {Array} props The property names.
* @param {Array} [values=[]] The property values.
* @returns {Object} Returns the new object.
* @example
*
* _.zipObject(['fred', 'barney'], [30, 40]);
* // => { 'fred': 30, 'barney': 40 }
*/
function zipObject(props, values) {
var index = -1,
length = props ? props.length : 0,
result = {};
if (length && !values && !isArray(props[0])) {
values = [];
}
while (++index < length) {
var key = props[index];
if (values) {
result[key] = values[index];
} else if (key) {
result[key[0]] = key[1];
}
}
return result;
}
/*------------------------------------------------------------------------*/
/**
* Creates a `lodash` object that wraps `value` with explicit method
* chaining enabled.
*
* @static
* @memberOf _
* @category Chain
* @param {*} value The value to wrap.
* @returns {Object} Returns the new `lodash` wrapper instance.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 },
* { 'user': 'pebbles', 'age': 1 }
* ];
*
* var youngest = _.chain(users)
* .sortBy('age')
* .map(function(chr) { return chr.user + ' is ' + chr.age; })
* .first()
* .value();
* // => 'pebbles is 1'
*/
function chain(value) {
var result = lodash(value);
result.__chain__ = true;
return result;
}
/**
* This method invokes `interceptor` and returns `value`. The interceptor is
* bound to `thisArg` and invoked with one argument; (value). The purpose of
* this method is to "tap into" a method chain in order to perform operations
* on intermediate results within the chain.
*
* @static
* @memberOf _
* @category Chain
* @param {*} value The value to provide to `interceptor`.
* @param {Function} interceptor The function to invoke.
* @param {*} [thisArg] The `this` binding of `interceptor`.
* @returns {*} Returns `value`.
* @example
*
* _([1, 2, 3])
* .tap(function(array) { array.pop(); })
* .reverse()
* .value();
* // => [2, 1]
*/
function tap(value, interceptor, thisArg) {
interceptor.call(thisArg, value);
return value;
}
/**
* This method is like `_.tap` except that it returns the result of `interceptor`.
*
* @static
* @memberOf _
* @category Chain
* @param {*} value The value to provide to `interceptor`.
* @param {Function} interceptor The function to invoke.
* @param {*} [thisArg] The `this` binding of `interceptor`.
* @returns {*} Returns the result of `interceptor`.
* @example
*
* _([1, 2, 3])
* .last()
* .thru(function(value) { return [value]; })
* .value();
* // => [3]
*/
function thru(value, interceptor, thisArg) {
return interceptor.call(thisArg, value);
}
/**
* Enables explicit method chaining on the wrapper object.
*
* @name chain
* @memberOf _
* @category Chain
* @returns {Object} Returns the new `lodash` wrapper instance.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* // without explicit chaining
* _(users).first();
* // => { 'user': 'barney', 'age': 36 }
*
* // with explicit chaining
* _(users).chain()
* .first()
* .pick('user')
* .value();
* // => { 'user': 'barney' }
*/
function wrapperChain() {
return chain(this);
}
/**
* Executes the chained sequence and returns the wrapped result.
*
* @name commit
* @memberOf _
* @category Chain
* @returns {Object} Returns the new `lodash` wrapper instance.
* @example
*
* var array = [1, 2];
* var wrapper = _(array).push(3);
*
* console.log(array);
* // => [1, 2]
*
* wrapper = wrapper.commit();
* console.log(array);
* // => [1, 2, 3]
*
* wrapper.last();
* // => 3
*
* console.log(array);
* // => [1, 2, 3]
*/
function wrapperCommit() {
return new LodashWrapper(this.value(), this.__chain__);
}
/**
* Creates a clone of the chained sequence planting `value` as the wrapped value.
*
* @name plant
* @memberOf _
* @category Chain
* @returns {Object} Returns the new `lodash` wrapper instance.
* @example
*
* var array = [1, 2];
* var wrapper = _(array).map(_.partial(Math.pow, _, 2));
*
* var other = [3, 4];
* var otherWrapper = wrapper.plant(other);
*
* otherWrapper.value();
* // => [9, 16]
*
* wrapper.value();
* // => [1, 4]
*/
function wrapperPlant(value) {
var result,
parent = this;
while (parent instanceof LodashWrapper) {
var clone = wrapperClone(parent);
if (result) {
previous.__wrapped__ = clone;
} else {
result = clone;
}
var previous = clone;
parent = parent.__wrapped__;
}
previous.__wrapped__ = value;
return result;
}
/**
* Reverses the wrapped array so the first element becomes the last, the
* second element becomes the second to last, and so on.
*
* **Note:** This method mutates the wrapped array.
*
* @name reverse
* @memberOf _
* @category Chain
* @returns {Object} Returns the new reversed `lodash` wrapper instance.
* @example
*
* var array = [1, 2, 3];
*
* _(array).reverse().value()
* // => [3, 2, 1]
*
* console.log(array);
* // => [3, 2, 1]
*/
function wrapperReverse() {
var value = this.__wrapped__;
if (value instanceof LazyWrapper) {
if (this.__actions__.length) {
value = new LazyWrapper(this);
}
return new LodashWrapper(value.reverse(), this.__chain__);
}
return this.thru(function(value) {
return value.reverse();
});
}
/**
* Produces the result of coercing the unwrapped value to a string.
*
* @name toString
* @memberOf _
* @category Chain
* @returns {string} Returns the coerced string value.
* @example
*
* _([1, 2, 3]).toString();
* // => '1,2,3'
*/
function wrapperToString() {
return (this.value() + '');
}
/**
* Executes the chained sequence to extract the unwrapped value.
*
* @name value
* @memberOf _
* @alias run, toJSON, valueOf
* @category Chain
* @returns {*} Returns the resolved unwrapped value.
* @example
*
* _([1, 2, 3]).value();
* // => [1, 2, 3]
*/
function wrapperValue() {
return baseWrapperValue(this.__wrapped__, this.__actions__);
}
/*------------------------------------------------------------------------*/
/**
* Creates an array of elements corresponding to the given keys, or indexes,
* of `collection`. Keys may be specified as individual arguments or as arrays
* of keys.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {...(number|number[]|string|string[])} [props] The property names
* or indexes of elements to pick, specified individually or in arrays.
* @returns {Array} Returns the new array of picked elements.
* @example
*
* _.at(['a', 'b', 'c', 'd', 'e'], [0, 2, 4]);
* // => ['a', 'c', 'e']
*
* _.at(['fred', 'barney', 'pebbles'], 0, 2);
* // => ['fred', 'pebbles']
*/
function at(collection) {
var length = collection ? collection.length : 0;
if (isLength(length)) {
collection = toIterable(collection);
}
return baseAt(collection, baseFlatten(arguments, false, false, 1));
}
/**
* Checks if `value` is in `collection` using `SameValueZero` for equality
* comparisons. If `fromIndex` is negative, it is used as the offset from
* the end of `collection`.
*
* **Note:** `SameValueZero` comparisons are like strict equality comparisons,
* e.g. `===`, except that `NaN` matches `NaN`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
* for more details.
*
* @static
* @memberOf _
* @alias contains, include
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {*} target The value to search for.
* @param {number} [fromIndex=0] The index to search from.
* @returns {boolean} Returns `true` if a matching element is found, else `false`.
* @example
*
* _.includes([1, 2, 3], 1);
* // => true
*
* _.includes([1, 2, 3], 1, 2);
* // => false
*
* _.includes({ 'user': 'fred', 'age': 40 }, 'fred');
* // => true
*
* _.includes('pebbles', 'eb');
* // => true
*/
function includes(collection, target, fromIndex) {
var length = collection ? collection.length : 0;
if (!isLength(length)) {
collection = values(collection);
length = collection.length;
}
if (!length) {
return false;
}
if (typeof fromIndex == 'number') {
fromIndex = fromIndex < 0 ? nativeMax(length + fromIndex, 0) : (fromIndex || 0);
} else {
fromIndex = 0;
}
return (typeof collection == 'string' || !isArray(collection) && isString(collection))
? (fromIndex < length && collection.indexOf(target, fromIndex) > -1)
: (getIndexOf(collection, target, fromIndex) > -1);
}
/**
* Creates an object composed of keys generated from the results of running
* each element of `collection` through `iteratee`. The corresponding value
* of each key is the number of times the key was returned by `iteratee`.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* _.countBy([4.3, 6.1, 6.4], function(n) { return Math.floor(n); });
* // => { '4': 1, '6': 2 }
*
* _.countBy([4.3, 6.1, 6.4], function(n) { return this.floor(n); }, Math);
* // => { '4': 1, '6': 2 }
*
* _.countBy(['one', 'two', 'three'], 'length');
* // => { '3': 2, '5': 1 }
*/
var countBy = createAggregator(function(result, value, key) {
hasOwnProperty.call(result, key) ? ++result[key] : (result[key] = 1);
});
/**
* Checks if `predicate` returns truthy for **all** elements of `collection`.
* The predicate is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @alias all
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {boolean} Returns `true` if all elements pass the predicate check,
* else `false`.
* @example
*
* _.every([true, 1, null, 'yes']);
* // => false
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': false }
* ];
*
* // using the "_.matches" callback shorthand
* _.every(users, { 'age': 36, 'active': false });
* // => false
*
* // using the "_.matchesProperty" callback shorthand
* _.every(users, 'active', false);
* // => true
*
* // using the "_.property" callback shorthand
* _.every(users, 'active');
* // => false
*/
function every(collection, predicate, thisArg) {
var func = isArray(collection) ? arrayEvery : baseEvery;
if (typeof predicate != 'function' || typeof thisArg != 'undefined') {
predicate = getCallback(predicate, thisArg, 3);
}
return func(collection, predicate);
}
/**
* Iterates over elements of `collection`, returning an array of all elements
* `predicate` returns truthy for. The predicate is bound to `thisArg` and
* invoked with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @alias select
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the new filtered array.
* @example
*
* var evens = _.filter([1, 2, 3, 4], function(n) { return n % 2 == 0; });
* // => [2, 4]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': true },
* { 'user': 'fred', 'age': 40, 'active': false }
* ];
*
* // using the "_.matches" callback shorthand
* _.pluck(_.filter(users, { 'age': 36, 'active': true }), 'user');
* // => ['barney']
*
* // using the "_.matchesProperty" callback shorthand
* _.pluck(_.filter(users, 'active', false), 'user');
* // => ['fred']
*
* // using the "_.property" callback shorthand
* _.pluck(_.filter(users, 'active'), 'user');
* // => ['barney']
*/
function filter(collection, predicate, thisArg) {
var func = isArray(collection) ? arrayFilter : baseFilter;
predicate = getCallback(predicate, thisArg, 3);
return func(collection, predicate);
}
/**
* Iterates over elements of `collection`, returning the first element
* `predicate` returns truthy for. The predicate is bound to `thisArg` and
* invoked with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @alias detect
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {*} Returns the matched element, else `undefined`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': true },
* { 'user': 'fred', 'age': 40, 'active': false },
* { 'user': 'pebbles', 'age': 1, 'active': true }
* ];
*
* _.result(_.find(users, function(chr) { return chr.age < 40; }), 'user');
* // => 'barney'
*
* // using the "_.matches" callback shorthand
* _.result(_.find(users, { 'age': 1, 'active': true }), 'user');
* // => 'pebbles'
*
* // using the "_.matchesProperty" callback shorthand
* _.result(_.find(users, 'active', false), 'user');
* // => 'fred'
*
* // using the "_.property" callback shorthand
* _.result(_.find(users, 'active'), 'user');
* // => 'barney'
*/
function find(collection, predicate, thisArg) {
if (isArray(collection)) {
var index = findIndex(collection, predicate, thisArg);
return index > -1 ? collection[index] : undefined;
}
predicate = getCallback(predicate, thisArg, 3);
return baseFind(collection, predicate, baseEach);
}
/**
* This method is like `_.find` except that it iterates over elements of
* `collection` from right to left.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {*} Returns the matched element, else `undefined`.
* @example
*
* _.findLast([1, 2, 3, 4], function(n) { return n % 2 == 1; });
* // => 3
*/
function findLast(collection, predicate, thisArg) {
predicate = getCallback(predicate, thisArg, 3);
return baseFind(collection, predicate, baseEachRight);
}
/**
* Performs a deep comparison between each element in `collection` and the
* source object, returning the first element that has equivalent property
* values.
*
* **Note:** This method supports comparing arrays, booleans, `Date` objects,
* numbers, `Object` objects, regexes, and strings. Objects are compared by
* their own, not inherited, enumerable properties. For comparing a single
* own or inherited property value see `_.matchesProperty`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Object} source The object of property values to match.
* @returns {*} Returns the matched element, else `undefined`.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': true },
* { 'user': 'fred', 'age': 40, 'active': false }
* ];
*
* _.result(_.findWhere(users, { 'age': 36, 'active': true }), 'user');
* // => 'barney'
*
* _.result(_.findWhere(users, { 'age': 40, 'active': false }), 'user');
* // => 'fred'
*/
function findWhere(collection, source) {
return find(collection, baseMatches(source));
}
/**
* Iterates over elements of `collection` invoking `iteratee` for each element.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection). Iterator functions may exit iteration early
* by explicitly returning `false`.
*
* **Note:** As with other "Collections" methods, objects with a `length` property
* are iterated like arrays. To avoid this behavior `_.forIn` or `_.forOwn`
* may be used for object iteration.
*
* @static
* @memberOf _
* @alias each
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array|Object|string} Returns `collection`.
* @example
*
* _([1, 2, 3]).forEach(function(n) { console.log(n); }).value();
* // => logs each value from left to right and returns the array
*
* _.forEach({ 'one': 1, 'two': 2, 'three': 3 }, function(n, key) { console.log(n, key); });
* // => logs each value-key pair and returns the object (iteration order is not guaranteed)
*/
function forEach(collection, iteratee, thisArg) {
return (typeof iteratee == 'function' && typeof thisArg == 'undefined' && isArray(collection))
? arrayEach(collection, iteratee)
: baseEach(collection, bindCallback(iteratee, thisArg, 3));
}
/**
* This method is like `_.forEach` except that it iterates over elements of
* `collection` from right to left.
*
* @static
* @memberOf _
* @alias eachRight
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array|Object|string} Returns `collection`.
* @example
*
* _([1, 2, 3]).forEachRight(function(n) { console.log(n); }).join(',');
* // => logs each value from right to left and returns the array
*/
function forEachRight(collection, iteratee, thisArg) {
return (typeof iteratee == 'function' && typeof thisArg == 'undefined' && isArray(collection))
? arrayEachRight(collection, iteratee)
: baseEachRight(collection, bindCallback(iteratee, thisArg, 3));
}
/**
* Creates an object composed of keys generated from the results of running
* each element of `collection` through `iteratee`. The corresponding value
* of each key is an array of the elements responsible for generating the key.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* _.groupBy([4.2, 6.1, 6.4], function(n) { return Math.floor(n); });
* // => { '4': [4.2], '6': [6.1, 6.4] }
*
* _.groupBy([4.2, 6.1, 6.4], function(n) { return this.floor(n); }, Math);
* // => { '4': [4.2], '6': [6.1, 6.4] }
*
* // using the "_.property" callback shorthand
* _.groupBy(['one', 'two', 'three'], 'length');
* // => { '3': ['one', 'two'], '5': ['three'] }
*/
var groupBy = createAggregator(function(result, value, key) {
if (hasOwnProperty.call(result, key)) {
result[key].push(value);
} else {
result[key] = [value];
}
});
/**
* Creates an object composed of keys generated from the results of running
* each element of `collection` through `iteratee`. The corresponding value
* of each key is the last element responsible for generating the key. The
* iteratee function is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* var keyData = [
* { 'dir': 'left', 'code': 97 },
* { 'dir': 'right', 'code': 100 }
* ];
*
* _.indexBy(keyData, 'dir');
* // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
*
* _.indexBy(keyData, function(object) { return String.fromCharCode(object.code); });
* // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
*
* _.indexBy(keyData, function(object) { return this.fromCharCode(object.code); }, String);
* // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
*/
var indexBy = createAggregator(function(result, value, key) {
result[key] = value;
});
/**
* Invokes the method named by `methodName` on each element in `collection`,
* returning an array of the results of each invoked method. Any additional
* arguments are provided to each invoked method. If `methodName` is a function
* it is invoked for, and `this` bound to, each element in `collection`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|string} methodName The name of the method to invoke or
* the function invoked per iteration.
* @param {...*} [args] The arguments to invoke the method with.
* @returns {Array} Returns the array of results.
* @example
*
* _.invoke([[5, 1, 7], [3, 2, 1]], 'sort');
* // => [[1, 5, 7], [1, 2, 3]]
*
* _.invoke([123, 456], String.prototype.split, '');
* // => [['1', '2', '3'], ['4', '5', '6']]
*/
function invoke(collection, methodName) {
return baseInvoke(collection, methodName, baseSlice(arguments, 2));
}
/**
* Creates an array of values by running each element in `collection` through
* `iteratee`. The `iteratee` is bound to `thisArg` and invoked with three
* arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* Many lodash methods are guarded to work as interatees for methods like
* `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`.
*
* The guarded methods are:
* `ary`, `callback`, `chunk`, `clone`, `create`, `curry`, `curryRight`, `drop`,
* `dropRight`, `fill`, `flatten`, `invert`, `max`, `min`, `parseInt`, `slice`,
* `sortBy`, `take`, `takeRight`, `template`, `trim`, `trimLeft`, `trimRight`,
* `trunc`, `random`, `range`, `sample`, `uniq`, and `words`
*
* @static
* @memberOf _
* @alias collect
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array} Returns the new mapped array.
* @example
*
* _.map([1, 2, 3], function(n) { return n * 3; });
* // => [3, 6, 9]
*
* _.map({ 'one': 1, 'two': 2, 'three': 3 }, function(n) { return n * 3; });
* // => [3, 6, 9] (iteration order is not guaranteed)
*
* var users = [
* { 'user': 'barney' },
* { 'user': 'fred' }
* ];
*
* // using the "_.property" callback shorthand
* _.map(users, 'user');
* // => ['barney', 'fred']
*/
function map(collection, iteratee, thisArg) {
var func = isArray(collection) ? arrayMap : baseMap;
iteratee = getCallback(iteratee, thisArg, 3);
return func(collection, iteratee);
}
/**
* Gets the maximum value of `collection`. If `collection` is empty or falsey
* `-Infinity` is returned. If an iteratee function is provided it is invoked
* for each value in `collection` to generate the criterion by which the value
* is ranked. The `iteratee` is bound to `thisArg` and invoked with three
* arguments; (value, index, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee] The function invoked per iteration.
* If a property name or object is provided it is used to create a "_.property"
* or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the maximum value.
* @example
*
* _.max([4, 2, 8, 6]);
* // => 8
*
* _.max([]);
* // => -Infinity
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* _.max(users, function(chr) { return chr.age; });
* // => { 'user': 'fred', 'age': 40 };
*
* // using the "_.property" callback shorthand
* _.max(users, 'age');
* // => { 'user': 'fred', 'age': 40 };
*/
var max = createExtremum(arrayMax);
/**
* Gets the minimum value of `collection`. If `collection` is empty or falsey
* `Infinity` is returned. If an iteratee function is provided it is invoked
* for each value in `collection` to generate the criterion by which the value
* is ranked. The `iteratee` is bound to `thisArg` and invoked with three
* arguments; (value, index, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [iteratee] The function invoked per iteration.
* If a property name or object is provided it is used to create a "_.property"
* or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the minimum value.
* @example
*
* _.min([4, 2, 8, 6]);
* // => 2
*
* _.min([]);
* // => Infinity
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* _.min(users, function(chr) { return chr.age; });
* // => { 'user': 'barney', 'age': 36 };
*
* // using the "_.property" callback shorthand
* _.min(users, 'age');
* // => { 'user': 'barney', 'age': 36 };
*/
var min = createExtremum(arrayMin, true);
/**
* Creates an array of elements split into two groups, the first of which
* contains elements `predicate` returns truthy for, while the second of which
* contains elements `predicate` returns falsey for. The predicate is bound
* to `thisArg` and invoked with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the array of grouped elements.
* @example
*
* _.partition([1, 2, 3], function(n) { return n % 2; });
* // => [[1, 3], [2]]
*
* _.partition([1.2, 2.3, 3.4], function(n) { return this.floor(n) % 2; }, Math);
* // => [[1, 3], [2]]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': true },
* { 'user': 'pebbles', 'age': 1, 'active': false }
* ];
*
* var mapper = function(array) { return _.pluck(array, 'user'); };
*
* // using the "_.matches" callback shorthand
* _.map(_.partition(users, { 'age': 1, 'active': false }), mapper);
* // => [['pebbles'], ['barney', 'fred']]
*
* // using the "_.matchesProperty" callback shorthand
* _.map(_.partition(users, 'active', false), mapper);
* // => [['barney', 'pebbles'], ['fred']]
*
* // using the "_.property" callback shorthand
* _.map(_.partition(users, 'active'), mapper);
* // => [['fred'], ['barney', 'pebbles']]
*/
var partition = createAggregator(function(result, value, key) {
result[key ? 0 : 1].push(value);
}, function() { return [[], []]; });
/**
* Gets the value of `key` from all elements in `collection`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {string} key The key of the property to pluck.
* @returns {Array} Returns the property values.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 }
* ];
*
* _.pluck(users, 'user');
* // => ['barney', 'fred']
*
* var userIndex = _.indexBy(users, 'user');
* _.pluck(userIndex, 'age');
* // => [36, 40] (iteration order is not guaranteed)
*/
function pluck(collection, key) {
return map(collection, baseProperty(key));
}
/**
* Reduces `collection` to a value which is the accumulated result of running
* each element in `collection` through `iteratee`, where each successive
* invocation is supplied the return value of the previous. If `accumulator`
* is not provided the first element of `collection` is used as the initial
* value. The `iteratee` is bound to `thisArg`and invoked with four arguments;
* (accumulator, value, index|key, collection).
*
* Many lodash methods are guarded to work as interatees for methods like
* `_.reduce`, `_.reduceRight`, and `_.transform`.
*
* The guarded methods are:
* `assign`, `defaults`, `merge`, and `sortAllBy`
*
* @static
* @memberOf _
* @alias foldl, inject
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the accumulated value.
* @example
*
* var sum = _.reduce([1, 2, 3], function(sum, n) { return sum + n; });
* // => 6
*
* var mapped = _.reduce({ 'a': 1, 'b': 2, 'c': 3 }, function(result, n, key) {
* result[key] = n * 3;
* return result;
* }, {});
* // => { 'a': 3, 'b': 6, 'c': 9 } (iteration order is not guaranteed)
*/
function reduce(collection, iteratee, accumulator, thisArg) {
var func = isArray(collection) ? arrayReduce : baseReduce;
return func(collection, getCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEach);
}
/**
* This method is like `_.reduce` except that it iterates over elements of
* `collection` from right to left.
*
* @static
* @memberOf _
* @alias foldr
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [accumulator] The initial value.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the accumulated value.
* @example
*
* var array = [[0, 1], [2, 3], [4, 5]];
* _.reduceRight(array, function(flattened, other) { return flattened.concat(other); }, []);
* // => [4, 5, 2, 3, 0, 1]
*/
function reduceRight(collection, iteratee, accumulator, thisArg) {
var func = isArray(collection) ? arrayReduceRight : baseReduce;
return func(collection, getCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEachRight);
}
/**
* The opposite of `_.filter`; this method returns the elements of `collection`
* that `predicate` does **not** return truthy for.
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Array} Returns the new filtered array.
* @example
*
* var odds = _.reject([1, 2, 3, 4], function(n) { return n % 2 == 0; });
* // => [1, 3]
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': true }
* ];
*
* // using the "_.matches" callback shorthand
* _.pluck(_.reject(users, { 'age': 40, 'active': true }), 'user');
* // => ['barney']
*
* // using the "_.matchesProperty" callback shorthand
* _.pluck(_.reject(users, 'active', false), 'user');
* // => ['fred']
*
* // using the "_.property" callback shorthand
* _.pluck(_.reject(users, 'active'), 'user');
* // => ['barney']
*/
function reject(collection, predicate, thisArg) {
var func = isArray(collection) ? arrayFilter : baseFilter;
predicate = getCallback(predicate, thisArg, 3);
return func(collection, function(value, index, collection) {
return !predicate(value, index, collection);
});
}
/**
* Gets a random element or `n` random elements from a collection.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to sample.
* @param {number} [n] The number of elements to sample.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {*} Returns the random sample(s).
* @example
*
* _.sample([1, 2, 3, 4]);
* // => 2
*
* _.sample([1, 2, 3, 4], 2);
* // => [3, 1]
*/
function sample(collection, n, guard) {
if (guard ? isIterateeCall(collection, n, guard) : n == null) {
collection = toIterable(collection);
var length = collection.length;
return length > 0 ? collection[baseRandom(0, length - 1)] : undefined;
}
var result = shuffle(collection);
result.length = nativeMin(n < 0 ? 0 : (+n || 0), result.length);
return result;
}
/**
* Creates an array of shuffled values, using a version of the Fisher-Yates
* shuffle. See [Wikipedia](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle)
* for more details.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to shuffle.
* @returns {Array} Returns the new shuffled array.
* @example
*
* _.shuffle([1, 2, 3, 4]);
* // => [4, 1, 3, 2]
*/
function shuffle(collection) {
collection = toIterable(collection);
var index = -1,
length = collection.length,
result = Array(length);
while (++index < length) {
var rand = baseRandom(0, index);
if (index != rand) {
result[index] = result[rand];
}
result[rand] = collection[index];
}
return result;
}
/**
* Gets the size of `collection` by returning `collection.length` for
* array-like values or the number of own enumerable properties for objects.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to inspect.
* @returns {number} Returns the size of `collection`.
* @example
*
* _.size([1, 2]);
* // => 2
*
* _.size({ 'one': 1, 'two': 2, 'three': 3 });
* // => 3
*
* _.size('pebbles');
* // => 7
*/
function size(collection) {
var length = collection ? collection.length : 0;
return isLength(length) ? length : keys(collection).length;
}
/**
* Checks if `predicate` returns truthy for **any** element of `collection`.
* The function returns as soon as it finds a passing value and does not iterate
* over the entire collection. The predicate is bound to `thisArg` and invoked
* with three arguments; (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @alias any
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {boolean} Returns `true` if any element passes the predicate check,
* else `false`.
* @example
*
* _.some([null, 0, 'yes', false], Boolean);
* // => true
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false },
* { 'user': 'fred', 'age': 40, 'active': true }
* ];
*
* // using the "_.matches" callback shorthand
* _.some(users, { 'age': 1, 'active': true });
* // => false
*
* // using the "_.matchesProperty" callback shorthand
* _.some(users, 'active', false);
* // => true
*
* // using the "_.property" callback shorthand
* _.some(users, 'active');
* // => true
*/
function some(collection, predicate, thisArg) {
var func = isArray(collection) ? arraySome : baseSome;
if (typeof predicate != 'function' || typeof thisArg != 'undefined') {
predicate = getCallback(predicate, thisArg, 3);
}
return func(collection, predicate);
}
/**
* Creates an array of elements, sorted in ascending order by the results of
* running each element in a collection through `iteratee`. This method performs
* a stable sort, that is, it preserves the original sort order of equal elements.
* The `iteratee` is bound to `thisArg` and invoked with three arguments;
* (value, index|key, collection).
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {Array|Function|Object|string} [iteratee=_.identity] The function
* invoked per iteration. If a property name or an object is provided it is
* used to create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Array} Returns the new sorted array.
* @example
*
* _.sortBy([1, 2, 3], function(n) { return Math.sin(n); });
* // => [3, 1, 2]
*
* _.sortBy([1, 2, 3], function(n) { return this.sin(n); }, Math);
* // => [3, 1, 2]
*
* var users = [
* { 'user': 'fred' },
* { 'user': 'pebbles' },
* { 'user': 'barney' }
* ];
*
* // using the "_.property" callback shorthand
* _.pluck(_.sortBy(users, 'user'), 'user');
* // => ['barney', 'fred', 'pebbles']
*/
function sortBy(collection, iteratee, thisArg) {
var index = -1,
length = collection ? collection.length : 0,
result = isLength(length) ? Array(length) : [];
if (thisArg && isIterateeCall(collection, iteratee, thisArg)) {
iteratee = null;
}
iteratee = getCallback(iteratee, thisArg, 3);
baseEach(collection, function(value, key, collection) {
result[++index] = { 'criteria': iteratee(value, key, collection), 'index': index, 'value': value };
});
return baseSortBy(result, compareAscending);
}
/**
* This method is like `_.sortBy` except that it sorts by property names
* instead of an iteratee function.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to iterate over.
* @param {...(string|string[])} props The property names to sort by,
* specified as individual property names or arrays of property names.
* @returns {Array} Returns the new sorted array.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36 },
* { 'user': 'fred', 'age': 40 },
* { 'user': 'barney', 'age': 26 },
* { 'user': 'fred', 'age': 30 }
* ];
*
* _.map(_.sortByAll(users, ['user', 'age']), _.values);
* // => [['barney', 26], ['barney', 36], ['fred', 30], ['fred', 40]]
*/
function sortByAll(collection) {
var args = arguments;
if (args.length > 3 && isIterateeCall(args[1], args[2], args[3])) {
args = [collection, args[1]];
}
var index = -1,
length = collection ? collection.length : 0,
props = baseFlatten(args, false, false, 1),
result = isLength(length) ? Array(length) : [];
baseEach(collection, function(value) {
var length = props.length,
criteria = Array(length);
while (length--) {
criteria[length] = value == null ? undefined : value[props[length]];
}
result[++index] = { 'criteria': criteria, 'index': index, 'value': value };
});
return baseSortBy(result, compareMultipleAscending);
}
/**
* Performs a deep comparison between each element in `collection` and the
* source object, returning an array of all elements that have equivalent
* property values.
*
* **Note:** This method supports comparing arrays, booleans, `Date` objects,
* numbers, `Object` objects, regexes, and strings. Objects are compared by
* their own, not inherited, enumerable properties. For comparing a single
* own or inherited property value see `_.matchesProperty`.
*
* @static
* @memberOf _
* @category Collection
* @param {Array|Object|string} collection The collection to search.
* @param {Object} source The object of property values to match.
* @returns {Array} Returns the new filtered array.
* @example
*
* var users = [
* { 'user': 'barney', 'age': 36, 'active': false, 'pets': ['hoppy'] },
* { 'user': 'fred', 'age': 40, 'active': true, 'pets': ['baby puss', 'dino'] }
* ];
*
* _.pluck(_.where(users, { 'age': 36, 'active': false }), 'user');
* // => ['barney']
*
* _.pluck(_.where(users, { 'pets': ['dino'] }), 'user');
* // => ['fred']
*/
function where(collection, source) {
return filter(collection, baseMatches(source));
}
/*------------------------------------------------------------------------*/
/**
* Gets the number of milliseconds that have elapsed since the Unix epoch
* (1 January 1970 00:00:00 UTC).
*
* @static
* @memberOf _
* @category Date
* @example
*
* _.defer(function(stamp) { console.log(_.now() - stamp); }, _.now());
* // => logs the number of milliseconds it took for the deferred function to be invoked
*/
var now = nativeNow || function() {
return new Date().getTime();
};
/*------------------------------------------------------------------------*/
/**
* The opposite of `_.before`; this method creates a function that invokes
* `func` once it is called `n` or more times.
*
* @static
* @memberOf _
* @category Function
* @param {number} n The number of calls before `func` is invoked.
* @param {Function} func The function to restrict.
* @returns {Function} Returns the new restricted function.
* @example
*
* var saves = ['profile', 'settings'];
*
* var done = _.after(saves.length, function() {
* console.log('done saving!');
* });
*
* _.forEach(saves, function(type) {
* asyncSave({ 'type': type, 'complete': done });
* });
* // => logs 'done saving!' after the two async saves have completed
*/
function after(n, func) {
if (typeof func != 'function') {
if (typeof n == 'function') {
var temp = n;
n = func;
func = temp;
} else {
throw new TypeError(FUNC_ERROR_TEXT);
}
}
n = nativeIsFinite(n = +n) ? n : 0;
return function() {
if (--n < 1) {
return func.apply(this, arguments);
}
};
}
/**
* Creates a function that accepts up to `n` arguments ignoring any
* additional arguments.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to cap arguments for.
* @param {number} [n=func.length] The arity cap.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Function} Returns the new function.
* @example
*
* _.map(['6', '8', '10'], _.ary(parseInt, 1));
* // => [6, 8, 10]
*/
function ary(func, n, guard) {
if (guard && isIterateeCall(func, n, guard)) {
n = null;
}
n = (func && n == null) ? func.length : nativeMax(+n || 0, 0);
return createWrapper(func, ARY_FLAG, null, null, null, null, n);
}
/**
* Creates a function that invokes `func`, with the `this` binding and arguments
* of the created function, while it is called less than `n` times. Subsequent
* calls to the created function return the result of the last `func` invocation.
*
* @static
* @memberOf _
* @category Function
* @param {number} n The number of calls at which `func` is no longer invoked.
* @param {Function} func The function to restrict.
* @returns {Function} Returns the new restricted function.
* @example
*
* jQuery('#add').on('click', _.before(5, addContactToList));
* // => allows adding up to 4 contacts to the list
*/
function before(n, func) {
var result;
if (typeof func != 'function') {
if (typeof n == 'function') {
var temp = n;
n = func;
func = temp;
} else {
throw new TypeError(FUNC_ERROR_TEXT);
}
}
return function() {
if (--n > 0) {
result = func.apply(this, arguments);
} else {
func = null;
}
return result;
};
}
/**
* Creates a function that invokes `func` with the `this` binding of `thisArg`
* and prepends any additional `_.bind` arguments to those provided to the
* bound function.
*
* The `_.bind.placeholder` value, which defaults to `_` in monolithic builds,
* may be used as a placeholder for partially applied arguments.
*
* **Note:** Unlike native `Function#bind` this method does not set the `length`
* property of bound functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to bind.
* @param {*} thisArg The `this` binding of `func`.
* @param {...*} [args] The arguments to be partially applied.
* @returns {Function} Returns the new bound function.
* @example
*
* var greet = function(greeting, punctuation) {
* return greeting + ' ' + this.user + punctuation;
* };
*
* var object = { 'user': 'fred' };
*
* var bound = _.bind(greet, object, 'hi');
* bound('!');
* // => 'hi fred!'
*
* // using placeholders
* var bound = _.bind(greet, object, _, '!');
* bound('hi');
* // => 'hi fred!'
*/
function bind(func, thisArg) {
var bitmask = BIND_FLAG;
if (arguments.length > 2) {
var partials = baseSlice(arguments, 2),
holders = replaceHolders(partials, bind.placeholder);
bitmask |= PARTIAL_FLAG;
}
return createWrapper(func, bitmask, thisArg, partials, holders);
}
/**
* Binds methods of an object to the object itself, overwriting the existing
* method. Method names may be specified as individual arguments or as arrays
* of method names. If no method names are provided all enumerable function
* properties, own and inherited, of `object` are bound.
*
* **Note:** This method does not set the `length` property of bound functions.
*
* @static
* @memberOf _
* @category Function
* @param {Object} object The object to bind and assign the bound methods to.
* @param {...(string|string[])} [methodNames] The object method names to bind,
* specified as individual method names or arrays of method names.
* @returns {Object} Returns `object`.
* @example
*
* var view = {
* 'label': 'docs',
* 'onClick': function() { console.log('clicked ' + this.label); }
* };
*
* _.bindAll(view);
* jQuery('#docs').on('click', view.onClick);
* // => logs 'clicked docs' when the element is clicked
*/
function bindAll(object) {
return baseBindAll(object,
arguments.length > 1
? baseFlatten(arguments, false, false, 1)
: functions(object)
);
}
/**
* Creates a function that invokes the method at `object[key]` and prepends
* any additional `_.bindKey` arguments to those provided to the bound function.
*
* This method differs from `_.bind` by allowing bound functions to reference
* methods that may be redefined or don't yet exist.
* See [Peter Michaux's article](http://michaux.ca/articles/lazy-function-definition-pattern)
* for more details.
*
* The `_.bindKey.placeholder` value, which defaults to `_` in monolithic
* builds, may be used as a placeholder for partially applied arguments.
*
* @static
* @memberOf _
* @category Function
* @param {Object} object The object the method belongs to.
* @param {string} key The key of the method.
* @param {...*} [args] The arguments to be partially applied.
* @returns {Function} Returns the new bound function.
* @example
*
* var object = {
* 'user': 'fred',
* 'greet': function(greeting, punctuation) {
* return greeting + ' ' + this.user + punctuation;
* }
* };
*
* var bound = _.bindKey(object, 'greet', 'hi');
* bound('!');
* // => 'hi fred!'
*
* object.greet = function(greeting, punctuation) {
* return greeting + 'ya ' + this.user + punctuation;
* };
*
* bound('!');
* // => 'hiya fred!'
*
* // using placeholders
* var bound = _.bindKey(object, 'greet', _, '!');
* bound('hi');
* // => 'hiya fred!'
*/
function bindKey(object, key) {
var bitmask = BIND_FLAG | BIND_KEY_FLAG;
if (arguments.length > 2) {
var partials = baseSlice(arguments, 2),
holders = replaceHolders(partials, bindKey.placeholder);
bitmask |= PARTIAL_FLAG;
}
return createWrapper(key, bitmask, object, partials, holders);
}
/**
* Creates a function that accepts one or more arguments of `func` that when
* called either invokes `func` returning its result, if all `func` arguments
* have been provided, or returns a function that accepts one or more of the
* remaining `func` arguments, and so on. The arity of `func` may be specified
* if `func.length` is not sufficient.
*
* The `_.curry.placeholder` value, which defaults to `_` in monolithic builds,
* may be used as a placeholder for provided arguments.
*
* **Note:** This method does not set the `length` property of curried functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to curry.
* @param {number} [arity=func.length] The arity of `func`.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Function} Returns the new curried function.
* @example
*
* var abc = function(a, b, c) {
* return [a, b, c];
* };
*
* var curried = _.curry(abc);
*
* curried(1)(2)(3);
* // => [1, 2, 3]
*
* curried(1, 2)(3);
* // => [1, 2, 3]
*
* curried(1, 2, 3);
* // => [1, 2, 3]
*
* // using placeholders
* curried(1)(_, 3)(2);
* // => [1, 2, 3]
*/
function curry(func, arity, guard) {
if (guard && isIterateeCall(func, arity, guard)) {
arity = null;
}
var result = createWrapper(func, CURRY_FLAG, null, null, null, null, null, arity);
result.placeholder = curry.placeholder;
return result;
}
/**
* This method is like `_.curry` except that arguments are applied to `func`
* in the manner of `_.partialRight` instead of `_.partial`.
*
* The `_.curryRight.placeholder` value, which defaults to `_` in monolithic
* builds, may be used as a placeholder for provided arguments.
*
* **Note:** This method does not set the `length` property of curried functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to curry.
* @param {number} [arity=func.length] The arity of `func`.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Function} Returns the new curried function.
* @example
*
* var abc = function(a, b, c) {
* return [a, b, c];
* };
*
* var curried = _.curryRight(abc);
*
* curried(3)(2)(1);
* // => [1, 2, 3]
*
* curried(2, 3)(1);
* // => [1, 2, 3]
*
* curried(1, 2, 3);
* // => [1, 2, 3]
*
* // using placeholders
* curried(3)(1, _)(2);
* // => [1, 2, 3]
*/
function curryRight(func, arity, guard) {
if (guard && isIterateeCall(func, arity, guard)) {
arity = null;
}
var result = createWrapper(func, CURRY_RIGHT_FLAG, null, null, null, null, null, arity);
result.placeholder = curryRight.placeholder;
return result;
}
/**
* Creates a function that delays invoking `func` until after `wait` milliseconds
* have elapsed since the last time it was invoked. The created function comes
* with a `cancel` method to cancel delayed invocations. Provide an options
* object to indicate that `func` should be invoked on the leading and/or
* trailing edge of the `wait` timeout. Subsequent calls to the debounced
* function return the result of the last `func` invocation.
*
* **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
* on the trailing edge of the timeout only if the the debounced function is
* invoked more than once during the `wait` timeout.
*
* See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
* for details over the differences between `_.debounce` and `_.throttle`.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to debounce.
* @param {number} wait The number of milliseconds to delay.
* @param {Object} [options] The options object.
* @param {boolean} [options.leading=false] Specify invoking on the leading
* edge of the timeout.
* @param {number} [options.maxWait] The maximum time `func` is allowed to be
* delayed before it is invoked.
* @param {boolean} [options.trailing=true] Specify invoking on the trailing
* edge of the timeout.
* @returns {Function} Returns the new debounced function.
* @example
*
* // avoid costly calculations while the window size is in flux
* jQuery(window).on('resize', _.debounce(calculateLayout, 150));
*
* // invoke `sendMail` when the click event is fired, debouncing subsequent calls
* jQuery('#postbox').on('click', _.debounce(sendMail, 300, {
* 'leading': true,
* 'trailing': false
* }));
*
* // ensure `batchLog` is invoked once after 1 second of debounced calls
* var source = new EventSource('/stream');
* jQuery(source).on('message', _.debounce(batchLog, 250, {
* 'maxWait': 1000
* }));
*
* // cancel a debounced call
* var todoChanges = _.debounce(batchLog, 1000);
* Object.observe(models.todo, todoChanges);
*
* Object.observe(models, function(changes) {
* if (_.find(changes, { 'user': 'todo', 'type': 'delete'})) {
* todoChanges.cancel();
* }
* }, ['delete']);
*
* // ...at some point `models.todo` is changed
* models.todo.completed = true;
*
* // ...before 1 second has passed `models.todo` is deleted
* // which cancels the debounced `todoChanges` call
* delete models.todo;
*/
function debounce(func, wait, options) {
var args,
maxTimeoutId,
result,
stamp,
thisArg,
timeoutId,
trailingCall,
lastCalled = 0,
maxWait = false,
trailing = true;
if (typeof func != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
wait = wait < 0 ? 0 : wait;
if (options === true) {
var leading = true;
trailing = false;
} else if (isObject(options)) {
leading = options.leading;
maxWait = 'maxWait' in options && nativeMax(+options.maxWait || 0, wait);
trailing = 'trailing' in options ? options.trailing : trailing;
}
function cancel() {
if (timeoutId) {
clearTimeout(timeoutId);
}
if (maxTimeoutId) {
clearTimeout(maxTimeoutId);
}
maxTimeoutId = timeoutId = trailingCall = undefined;
}
function delayed() {
var remaining = wait - (now() - stamp);
if (remaining <= 0 || remaining > wait) {
if (maxTimeoutId) {
clearTimeout(maxTimeoutId);
}
var isCalled = trailingCall;
maxTimeoutId = timeoutId = trailingCall = undefined;
if (isCalled) {
lastCalled = now();
result = func.apply(thisArg, args);
if (!timeoutId && !maxTimeoutId) {
args = thisArg = null;
}
}
} else {
timeoutId = setTimeout(delayed, remaining);
}
}
function maxDelayed() {
if (timeoutId) {
clearTimeout(timeoutId);
}
maxTimeoutId = timeoutId = trailingCall = undefined;
if (trailing || (maxWait !== wait)) {
lastCalled = now();
result = func.apply(thisArg, args);
if (!timeoutId && !maxTimeoutId) {
args = thisArg = null;
}
}
}
function debounced() {
args = arguments;
stamp = now();
thisArg = this;
trailingCall = trailing && (timeoutId || !leading);
if (maxWait === false) {
var leadingCall = leading && !timeoutId;
} else {
if (!maxTimeoutId && !leading) {
lastCalled = stamp;
}
var remaining = maxWait - (stamp - lastCalled),
isCalled = remaining <= 0 || remaining > maxWait;
if (isCalled) {
if (maxTimeoutId) {
maxTimeoutId = clearTimeout(maxTimeoutId);
}
lastCalled = stamp;
result = func.apply(thisArg, args);
}
else if (!maxTimeoutId) {
maxTimeoutId = setTimeout(maxDelayed, remaining);
}
}
if (isCalled && timeoutId) {
timeoutId = clearTimeout(timeoutId);
}
else if (!timeoutId && wait !== maxWait) {
timeoutId = setTimeout(delayed, wait);
}
if (leadingCall) {
isCalled = true;
result = func.apply(thisArg, args);
}
if (isCalled && !timeoutId && !maxTimeoutId) {
args = thisArg = null;
}
return result;
}
debounced.cancel = cancel;
return debounced;
}
/**
* Defers invoking the `func` until the current call stack has cleared. Any
* additional arguments are provided to `func` when it is invoked.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to defer.
* @param {...*} [args] The arguments to invoke the function with.
* @returns {number} Returns the timer id.
* @example
*
* _.defer(function(text) { console.log(text); }, 'deferred');
* // logs 'deferred' after one or more milliseconds
*/
function defer(func) {
return baseDelay(func, 1, arguments, 1);
}
/**
* Invokes `func` after `wait` milliseconds. Any additional arguments are
* provided to `func` when it is invoked.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to delay.
* @param {number} wait The number of milliseconds to delay invocation.
* @param {...*} [args] The arguments to invoke the function with.
* @returns {number} Returns the timer id.
* @example
*
* _.delay(function(text) { console.log(text); }, 1000, 'later');
* // => logs 'later' after one second
*/
function delay(func, wait) {
return baseDelay(func, wait, arguments, 2);
}
/**
* Creates a function that returns the result of invoking the provided
* functions with the `this` binding of the created function, where each
* successive invocation is supplied the return value of the previous.
*
* @static
* @memberOf _
* @category Function
* @param {...Function} [funcs] Functions to invoke.
* @returns {Function} Returns the new function.
* @example
*
* function add(x, y) {
* return x + y;
* }
*
* function square(n) {
* return n * n;
* }
*
* var addSquare = _.flow(add, square);
* addSquare(1, 2);
* // => 9
*/
function flow() {
var funcs = arguments,
length = funcs.length;
if (!length) {
return function() { return arguments[0]; };
}
if (!arrayEvery(funcs, isFunction)) {
throw new TypeError(FUNC_ERROR_TEXT);
}
return function() {
var index = 0,
result = funcs[index].apply(this, arguments);
while (++index < length) {
result = funcs[index].call(this, result);
}
return result;
};
}
/**
* This method is like `_.flow` except that it creates a function that
* invokes the provided functions from right to left.
*
* @static
* @memberOf _
* @alias backflow, compose
* @category Function
* @param {...Function} [funcs] Functions to invoke.
* @returns {Function} Returns the new function.
* @example
*
* function add(x, y) {
* return x + y;
* }
*
* function square(n) {
* return n * n;
* }
*
* var addSquare = _.flowRight(square, add);
* addSquare(1, 2);
* // => 9
*/
function flowRight() {
var funcs = arguments,
fromIndex = funcs.length - 1;
if (fromIndex < 0) {
return function() { return arguments[0]; };
}
if (!arrayEvery(funcs, isFunction)) {
throw new TypeError(FUNC_ERROR_TEXT);
}
return function() {
var index = fromIndex,
result = funcs[index].apply(this, arguments);
while (index--) {
result = funcs[index].call(this, result);
}
return result;
};
}
/**
* Creates a function that memoizes the result of `func`. If `resolver` is
* provided it determines the cache key for storing the result based on the
* arguments provided to the memoized function. By default, the first argument
* provided to the memoized function is coerced to a string and used as the
* cache key. The `func` is invoked with the `this` binding of the memoized
* function.
*
* **Note:** The cache is exposed as the `cache` property on the memoized
* function. Its creation may be customized by replacing the `_.memoize.Cache`
* constructor with one whose instances implement the ES `Map` method interface
* of `get`, `has`, and `set`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-properties-of-the-map-prototype-object)
* for more details.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to have its output memoized.
* @param {Function} [resolver] The function to resolve the cache key.
* @returns {Function} Returns the new memoizing function.
* @example
*
* var upperCase = _.memoize(function(string) {
* return string.toUpperCase();
* });
*
* upperCase('fred');
* // => 'FRED'
*
* // modifying the result cache
* upperCase.cache.set('fred', 'BARNEY');
* upperCase('fred');
* // => 'BARNEY'
*
* // replacing `_.memoize.Cache`
* var object = { 'user': 'fred' };
* var other = { 'user': 'barney' };
* var identity = _.memoize(_.identity);
*
* identity(object);
* // => { 'user': 'fred' }
* identity(other);
* // => { 'user': 'fred' }
*
* _.memoize.Cache = WeakMap;
* var identity = _.memoize(_.identity);
*
* identity(object);
* // => { 'user': 'fred' }
* identity(other);
* // => { 'user': 'barney' }
*/
function memoize(func, resolver) {
if (typeof func != 'function' || (resolver && typeof resolver != 'function')) {
throw new TypeError(FUNC_ERROR_TEXT);
}
var memoized = function() {
var cache = memoized.cache,
key = resolver ? resolver.apply(this, arguments) : arguments[0];
if (cache.has(key)) {
return cache.get(key);
}
var result = func.apply(this, arguments);
cache.set(key, result);
return result;
};
memoized.cache = new memoize.Cache;
return memoized;
}
/**
* Creates a function that negates the result of the predicate `func`. The
* `func` predicate is invoked with the `this` binding and arguments of the
* created function.
*
* @static
* @memberOf _
* @category Function
* @param {Function} predicate The predicate to negate.
* @returns {Function} Returns the new function.
* @example
*
* function isEven(n) {
* return n % 2 == 0;
* }
*
* _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
* // => [1, 3, 5]
*/
function negate(predicate) {
if (typeof predicate != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
return function() {
return !predicate.apply(this, arguments);
};
}
/**
* Creates a function that is restricted to invoking `func` once. Repeat calls
* to the function return the value of the first call. The `func` is invoked
* with the `this` binding of the created function.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to restrict.
* @returns {Function} Returns the new restricted function.
* @example
*
* var initialize = _.once(createApplication);
* initialize();
* initialize();
* // `initialize` invokes `createApplication` once
*/
function once(func) {
return before(func, 2);
}
/**
* Creates a function that invokes `func` with `partial` arguments prepended
* to those provided to the new function. This method is like `_.bind` except
* it does **not** alter the `this` binding.
*
* The `_.partial.placeholder` value, which defaults to `_` in monolithic
* builds, may be used as a placeholder for partially applied arguments.
*
* **Note:** This method does not set the `length` property of partially
* applied functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to partially apply arguments to.
* @param {...*} [args] The arguments to be partially applied.
* @returns {Function} Returns the new partially applied function.
* @example
*
* var greet = function(greeting, name) {
* return greeting + ' ' + name;
* };
*
* var sayHelloTo = _.partial(greet, 'hello');
* sayHelloTo('fred');
* // => 'hello fred'
*
* // using placeholders
* var greetFred = _.partial(greet, _, 'fred');
* greetFred('hi');
* // => 'hi fred'
*/
function partial(func) {
var partials = baseSlice(arguments, 1),
holders = replaceHolders(partials, partial.placeholder);
return createWrapper(func, PARTIAL_FLAG, null, partials, holders);
}
/**
* This method is like `_.partial` except that partially applied arguments
* are appended to those provided to the new function.
*
* The `_.partialRight.placeholder` value, which defaults to `_` in monolithic
* builds, may be used as a placeholder for partially applied arguments.
*
* **Note:** This method does not set the `length` property of partially
* applied functions.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to partially apply arguments to.
* @param {...*} [args] The arguments to be partially applied.
* @returns {Function} Returns the new partially applied function.
* @example
*
* var greet = function(greeting, name) {
* return greeting + ' ' + name;
* };
*
* var greetFred = _.partialRight(greet, 'fred');
* greetFred('hi');
* // => 'hi fred'
*
* // using placeholders
* var sayHelloTo = _.partialRight(greet, 'hello', _);
* sayHelloTo('fred');
* // => 'hello fred'
*/
function partialRight(func) {
var partials = baseSlice(arguments, 1),
holders = replaceHolders(partials, partialRight.placeholder);
return createWrapper(func, PARTIAL_RIGHT_FLAG, null, partials, holders);
}
/**
* Creates a function that invokes `func` with arguments arranged according
* to the specified indexes where the argument value at the first index is
* provided as the first argument, the argument value at the second index is
* provided as the second argument, and so on.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to rearrange arguments for.
* @param {...(number|number[])} indexes The arranged argument indexes,
* specified as individual indexes or arrays of indexes.
* @returns {Function} Returns the new function.
* @example
*
* var rearged = _.rearg(function(a, b, c) {
* return [a, b, c];
* }, 2, 0, 1);
*
* rearged('b', 'c', 'a')
* // => ['a', 'b', 'c']
*
* var map = _.rearg(_.map, [1, 0]);
* map(function(n) { return n * 3; }, [1, 2, 3]);
* // => [3, 6, 9]
*/
function rearg(func) {
var indexes = baseFlatten(arguments, false, false, 1);
return createWrapper(func, REARG_FLAG, null, null, null, indexes);
}
/**
* Creates a function that invokes `func` with the `this` binding of the
* created function and the array of arguments provided to the created
* function much like [Function#apply](http://es5.github.io/#x15.3.4.3).
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to spread arguments over.
* @returns {*} Returns the new function.
* @example
*
* var spread = _.spread(function(who, what) {
* return who + ' says ' + what;
* });
*
* spread(['Fred', 'hello']);
* // => 'Fred says hello'
*
* // with a Promise
* var numbers = Promise.all([
* Promise.resolve(40),
* Promise.resolve(36)
* ]);
*
* var add = function(x, y) {
* return x + y;
* };
*
* numbers.then(_.spread(add));
* // => a Promise of 76
*/
function spread(func) {
if (typeof func != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
return function(array) {
return func.apply(this, array);
};
}
/**
* Creates a function that only invokes `func` at most once per every `wait`
* milliseconds. The created function comes with a `cancel` method to cancel
* delayed invocations. Provide an options object to indicate that `func`
* should be invoked on the leading and/or trailing edge of the `wait` timeout.
* Subsequent calls to the throttled function return the result of the last
* `func` call.
*
* **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
* on the trailing edge of the timeout only if the the throttled function is
* invoked more than once during the `wait` timeout.
*
* See [David Corbacho's article](http://drupalmotion.com/article/debounce-and-throttle-visual-explanation)
* for details over the differences between `_.throttle` and `_.debounce`.
*
* @static
* @memberOf _
* @category Function
* @param {Function} func The function to throttle.
* @param {number} wait The number of milliseconds to throttle invocations to.
* @param {Object} [options] The options object.
* @param {boolean} [options.leading=true] Specify invoking on the leading
* edge of the timeout.
* @param {boolean} [options.trailing=true] Specify invoking on the trailing
* edge of the timeout.
* @returns {Function} Returns the new throttled function.
* @example
*
* // avoid excessively updating the position while scrolling
* jQuery(window).on('scroll', _.throttle(updatePosition, 100));
*
* // invoke `renewToken` when the click event is fired, but not more than once every 5 minutes
* var throttled = _.throttle(renewToken, 300000, { 'trailing': false })
* jQuery('.interactive').on('click', throttled);
*
* // cancel a trailing throttled call
* jQuery(window).on('popstate', throttled.cancel);
*/
function throttle(func, wait, options) {
var leading = true,
trailing = true;
if (typeof func != 'function') {
throw new TypeError(FUNC_ERROR_TEXT);
}
if (options === false) {
leading = false;
} else if (isObject(options)) {
leading = 'leading' in options ? !!options.leading : leading;
trailing = 'trailing' in options ? !!options.trailing : trailing;
}
debounceOptions.leading = leading;
debounceOptions.maxWait = +wait;
debounceOptions.trailing = trailing;
return debounce(func, wait, debounceOptions);
}
/**
* Creates a function that provides `value` to the wrapper function as its
* first argument. Any additional arguments provided to the function are
* appended to those provided to the wrapper function. The wrapper is invoked
* with the `this` binding of the created function.
*
* @static
* @memberOf _
* @category Function
* @param {*} value The value to wrap.
* @param {Function} wrapper The wrapper function.
* @returns {Function} Returns the new function.
* @example
*
* var p = _.wrap(_.escape, function(func, text) {
* return '' + func(text) + '
';
* });
*
* p('fred, barney, & pebbles');
* // => 'fred, barney, & pebbles
'
*/
function wrap(value, wrapper) {
wrapper = wrapper == null ? identity : wrapper;
return createWrapper(wrapper, PARTIAL_FLAG, null, [value], []);
}
/*------------------------------------------------------------------------*/
/**
* Creates a clone of `value`. If `isDeep` is `true` nested objects are cloned,
* otherwise they are assigned by reference. If `customizer` is provided it is
* invoked to produce the cloned values. If `customizer` returns `undefined`
* cloning is handled by the method instead. The `customizer` is bound to
* `thisArg` and invoked with two argument; (value [, index|key, object]).
*
* **Note:** This method is loosely based on the structured clone algorithm.
* The enumerable properties of `arguments` objects and objects created by
* constructors other than `Object` are cloned to plain `Object` objects. An
* empty object is returned for uncloneable values such as functions, DOM nodes,
* Maps, Sets, and WeakMaps. See the [HTML5 specification](http://www.w3.org/TR/html5/infrastructure.html#internal-structured-cloning-algorithm)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to clone.
* @param {boolean} [isDeep] Specify a deep clone.
* @param {Function} [customizer] The function to customize cloning values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {*} Returns the cloned value.
* @example
*
* var users = [
* { 'user': 'barney' },
* { 'user': 'fred' }
* ];
*
* var shallow = _.clone(users);
* shallow[0] === users[0];
* // => true
*
* var deep = _.clone(users, true);
* deep[0] === users[0];
* // => false
*
* // using a customizer callback
* var body = _.clone(document.body, function(value) {
* return _.isElement(value) ? value.cloneNode(false) : undefined;
* });
*
* body === document.body
* // => false
* body.nodeName
* // => BODY
* body.childNodes.length;
* // => 0
*/
function clone(value, isDeep, customizer, thisArg) {
// Juggle arguments.
if (typeof isDeep != 'boolean' && isDeep != null) {
thisArg = customizer;
customizer = isIterateeCall(value, isDeep, thisArg) ? null : isDeep;
isDeep = false;
}
customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 1);
return baseClone(value, isDeep, customizer);
}
/**
* Creates a deep clone of `value`. If `customizer` is provided it is invoked
* to produce the cloned values. If `customizer` returns `undefined` cloning
* is handled by the method instead. The `customizer` is bound to `thisArg`
* and invoked with two argument; (value [, index|key, object]).
*
* **Note:** This method is loosely based on the structured clone algorithm.
* The enumerable properties of `arguments` objects and objects created by
* constructors other than `Object` are cloned to plain `Object` objects. An
* empty object is returned for uncloneable values such as functions, DOM nodes,
* Maps, Sets, and WeakMaps. See the [HTML5 specification](http://www.w3.org/TR/html5/infrastructure.html#internal-structured-cloning-algorithm)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to deep clone.
* @param {Function} [customizer] The function to customize cloning values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {*} Returns the deep cloned value.
* @example
*
* var users = [
* { 'user': 'barney' },
* { 'user': 'fred' }
* ];
*
* var deep = _.cloneDeep(users);
* deep[0] === users[0];
* // => false
*
* // using a customizer callback
* var el = _.cloneDeep(document.body, function(value) {
* return _.isElement(value) ? value.cloneNode(true) : undefined;
* });
*
* body === document.body
* // => false
* body.nodeName
* // => BODY
* body.childNodes.length;
* // => 20
*/
function cloneDeep(value, customizer, thisArg) {
customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 1);
return baseClone(value, true, customizer);
}
/**
* Checks if `value` is classified as an `arguments` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* (function() { return _.isArguments(arguments); })();
* // => true
*
* _.isArguments([1, 2, 3]);
* // => false
*/
function isArguments(value) {
var length = isObjectLike(value) ? value.length : undefined;
return (isLength(length) && objToString.call(value) == argsTag) || false;
}
/**
* Checks if `value` is classified as an `Array` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isArray([1, 2, 3]);
* // => true
*
* (function() { return _.isArray(arguments); })();
* // => false
*/
var isArray = nativeIsArray || function(value) {
return (isObjectLike(value) && isLength(value.length) && objToString.call(value) == arrayTag) || false;
};
/**
* Checks if `value` is classified as a boolean primitive or object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isBoolean(false);
* // => true
*
* _.isBoolean(null);
* // => false
*/
function isBoolean(value) {
return (value === true || value === false || isObjectLike(value) && objToString.call(value) == boolTag) || false;
}
/**
* Checks if `value` is classified as a `Date` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isDate(new Date);
* // => true
*
* _.isDate('Mon April 23 2012');
* // => false
*/
function isDate(value) {
return (isObjectLike(value) && objToString.call(value) == dateTag) || false;
}
/**
* Checks if `value` is a DOM element.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a DOM element, else `false`.
* @example
*
* _.isElement(document.body);
* // => true
*
* _.isElement('');
* // => false
*/
function isElement(value) {
return (value && value.nodeType === 1 && isObjectLike(value) &&
objToString.call(value).indexOf('Element') > -1) || false;
}
// Fallback for environments without DOM support.
if (!support.dom) {
isElement = function(value) {
return (value && value.nodeType === 1 && isObjectLike(value) && !isPlainObject(value)) || false;
};
}
/**
* Checks if a value is empty. A value is considered empty unless it is an
* `arguments` object, array, string, or jQuery-like collection with a length
* greater than `0` or an object with own enumerable properties.
*
* @static
* @memberOf _
* @category Lang
* @param {Array|Object|string} value The value to inspect.
* @returns {boolean} Returns `true` if `value` is empty, else `false`.
* @example
*
* _.isEmpty(null);
* // => true
*
* _.isEmpty(true);
* // => true
*
* _.isEmpty(1);
* // => true
*
* _.isEmpty([1, 2, 3]);
* // => false
*
* _.isEmpty({ 'a': 1 });
* // => false
*/
function isEmpty(value) {
if (value == null) {
return true;
}
var length = value.length;
if (isLength(length) && (isArray(value) || isString(value) || isArguments(value) ||
(isObjectLike(value) && isFunction(value.splice)))) {
return !length;
}
return !keys(value).length;
}
/**
* Performs a deep comparison between two values to determine if they are
* equivalent. If `customizer` is provided it is invoked to compare values.
* If `customizer` returns `undefined` comparisons are handled by the method
* instead. The `customizer` is bound to `thisArg` and invoked with three
* arguments; (value, other [, index|key]).
*
* **Note:** This method supports comparing arrays, booleans, `Date` objects,
* numbers, `Object` objects, regexes, and strings. Objects are compared by
* their own, not inherited, enumerable properties. Functions and DOM nodes
* are **not** supported. Provide a customizer function to extend support
* for comparing other values.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to compare.
* @param {*} other The other value to compare.
* @param {Function} [customizer] The function to customize comparing values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {boolean} Returns `true` if the values are equivalent, else `false`.
* @example
*
* var object = { 'user': 'fred' };
* var other = { 'user': 'fred' };
*
* object == other;
* // => false
*
* _.isEqual(object, other);
* // => true
*
* // using a customizer callback
* var array = ['hello', 'goodbye'];
* var other = ['hi', 'goodbye'];
*
* _.isEqual(array, other, function(value, other) {
* return _.every([value, other], RegExp.prototype.test, /^h(?:i|ello)$/) || undefined;
* });
* // => true
*/
function isEqual(value, other, customizer, thisArg) {
customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 3);
if (!customizer && isStrictComparable(value) && isStrictComparable(other)) {
return value === other;
}
var result = customizer ? customizer(value, other) : undefined;
return typeof result == 'undefined' ? baseIsEqual(value, other, customizer) : !!result;
}
/**
* Checks if `value` is an `Error`, `EvalError`, `RangeError`, `ReferenceError`,
* `SyntaxError`, `TypeError`, or `URIError` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is an error object, else `false`.
* @example
*
* _.isError(new Error);
* // => true
*
* _.isError(Error);
* // => false
*/
function isError(value) {
return (isObjectLike(value) && typeof value.message == 'string' && objToString.call(value) == errorTag) || false;
}
/**
* Checks if `value` is a finite primitive number.
*
* **Note:** This method is based on ES `Number.isFinite`. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.isfinite)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a finite number, else `false`.
* @example
*
* _.isFinite(10);
* // => true
*
* _.isFinite('10');
* // => false
*
* _.isFinite(true);
* // => false
*
* _.isFinite(Object(10));
* // => false
*
* _.isFinite(Infinity);
* // => false
*/
var isFinite = nativeNumIsFinite || function(value) {
return typeof value == 'number' && nativeIsFinite(value);
};
/**
* Checks if `value` is classified as a `Function` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isFunction(_);
* // => true
*
* _.isFunction(/abc/);
* // => false
*/
function isFunction(value) {
// Avoid a Chakra JIT bug in compatibility modes of IE 11.
// See https://github.com/jashkenas/underscore/issues/1621 for more details.
return typeof value == 'function' || false;
}
// Fallback for environments that return incorrect `typeof` operator results.
if (isFunction(/x/) || (Uint8Array && !isFunction(Uint8Array))) {
isFunction = function(value) {
// The use of `Object#toString` avoids issues with the `typeof` operator
// in older versions of Chrome and Safari which return 'function' for regexes
// and Safari 8 equivalents which return 'object' for typed array constructors.
return objToString.call(value) == funcTag;
};
}
/**
* Checks if `value` is the language type of `Object`.
* (e.g. arrays, functions, objects, regexes, `new Number(0)`, and `new String('')`)
*
* **Note:** See the [ES5 spec](https://es5.github.io/#x8) for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is an object, else `false`.
* @example
*
* _.isObject({});
* // => true
*
* _.isObject([1, 2, 3]);
* // => true
*
* _.isObject(1);
* // => false
*/
function isObject(value) {
// Avoid a V8 JIT bug in Chrome 19-20.
// See https://code.google.com/p/v8/issues/detail?id=2291 for more details.
var type = typeof value;
return type == 'function' || (value && type == 'object') || false;
}
/**
* Performs a deep comparison between `object` and `source` to determine if
* `object` contains equivalent property values. If `customizer` is provided
* it is invoked to compare values. If `customizer` returns `undefined`
* comparisons are handled by the method instead. The `customizer` is bound
* to `thisArg` and invoked with three arguments; (value, other, index|key).
*
* **Note:** This method supports comparing properties of arrays, booleans,
* `Date` objects, numbers, `Object` objects, regexes, and strings. Functions
* and DOM nodes are **not** supported. Provide a customizer function to extend
* support for comparing other values.
*
* @static
* @memberOf _
* @category Lang
* @param {Object} object The object to inspect.
* @param {Object} source The object of property values to match.
* @param {Function} [customizer] The function to customize comparing values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {boolean} Returns `true` if `object` is a match, else `false`.
* @example
*
* var object = { 'user': 'fred', 'age': 40 };
*
* _.isMatch(object, { 'age': 40 });
* // => true
*
* _.isMatch(object, { 'age': 36 });
* // => false
*
* // using a customizer callback
* var object = { 'greeting': 'hello' };
* var source = { 'greeting': 'hi' };
*
* _.isMatch(object, source, function(value, other) {
* return _.every([value, other], RegExp.prototype.test, /^h(?:i|ello)$/) || undefined;
* });
* // => true
*/
function isMatch(object, source, customizer, thisArg) {
var props = keys(source),
length = props.length;
customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 3);
if (!customizer && length == 1) {
var key = props[0],
value = source[key];
if (isStrictComparable(value)) {
return object != null && value === object[key] && hasOwnProperty.call(object, key);
}
}
var values = Array(length),
strictCompareFlags = Array(length);
while (length--) {
value = values[length] = source[props[length]];
strictCompareFlags[length] = isStrictComparable(value);
}
return baseIsMatch(object, props, values, strictCompareFlags, customizer);
}
/**
* Checks if `value` is `NaN`.
*
* **Note:** This method is not the same as native `isNaN` which returns `true`
* for `undefined` and other non-numeric values. See the [ES5 spec](https://es5.github.io/#x15.1.2.4)
* for more details.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
* @example
*
* _.isNaN(NaN);
* // => true
*
* _.isNaN(new Number(NaN));
* // => true
*
* isNaN(undefined);
* // => true
*
* _.isNaN(undefined);
* // => false
*/
function isNaN(value) {
// An `NaN` primitive is the only value that is not equal to itself.
// Perform the `toStringTag` check first to avoid errors with some host objects in IE.
return isNumber(value) && value != +value;
}
/**
* Checks if `value` is a native function.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a native function, else `false`.
* @example
*
* _.isNative(Array.prototype.push);
* // => true
*
* _.isNative(_);
* // => false
*/
function isNative(value) {
if (value == null) {
return false;
}
if (objToString.call(value) == funcTag) {
return reNative.test(fnToString.call(value));
}
return (isObjectLike(value) && reHostCtor.test(value)) || false;
}
/**
* Checks if `value` is `null`.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is `null`, else `false`.
* @example
*
* _.isNull(null);
* // => true
*
* _.isNull(void 0);
* // => false
*/
function isNull(value) {
return value === null;
}
/**
* Checks if `value` is classified as a `Number` primitive or object.
*
* **Note:** To exclude `Infinity`, `-Infinity`, and `NaN`, which are classified
* as numbers, use the `_.isFinite` method.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isNumber(8.4);
* // => true
*
* _.isNumber(NaN);
* // => true
*
* _.isNumber('8.4');
* // => false
*/
function isNumber(value) {
return typeof value == 'number' || (isObjectLike(value) && objToString.call(value) == numberTag) || false;
}
/**
* Checks if `value` is a plain object, that is, an object created by the
* `Object` constructor or one with a `[[Prototype]]` of `null`.
*
* **Note:** This method assumes objects created by the `Object` constructor
* have no inherited enumerable properties.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
* @example
*
* function Foo() {
* this.a = 1;
* }
*
* _.isPlainObject(new Foo);
* // => false
*
* _.isPlainObject([1, 2, 3]);
* // => false
*
* _.isPlainObject({ 'x': 0, 'y': 0 });
* // => true
*
* _.isPlainObject(Object.create(null));
* // => true
*/
var isPlainObject = !getPrototypeOf ? shimIsPlainObject : function(value) {
if (!(value && objToString.call(value) == objectTag)) {
return false;
}
var valueOf = value.valueOf,
objProto = isNative(valueOf) && (objProto = getPrototypeOf(valueOf)) && getPrototypeOf(objProto);
return objProto
? (value == objProto || getPrototypeOf(value) == objProto)
: shimIsPlainObject(value);
};
/**
* Checks if `value` is classified as a `RegExp` object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isRegExp(/abc/);
* // => true
*
* _.isRegExp('/abc/');
* // => false
*/
function isRegExp(value) {
return (isObjectLike(value) && objToString.call(value) == regexpTag) || false;
}
/**
* Checks if `value` is classified as a `String` primitive or object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isString('abc');
* // => true
*
* _.isString(1);
* // => false
*/
function isString(value) {
return typeof value == 'string' || (isObjectLike(value) && objToString.call(value) == stringTag) || false;
}
/**
* Checks if `value` is classified as a typed array.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is correctly classified, else `false`.
* @example
*
* _.isTypedArray(new Uint8Array);
* // => true
*
* _.isTypedArray([]);
* // => false
*/
function isTypedArray(value) {
return (isObjectLike(value) && isLength(value.length) && typedArrayTags[objToString.call(value)]) || false;
}
/**
* Checks if `value` is `undefined`.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to check.
* @returns {boolean} Returns `true` if `value` is `undefined`, else `false`.
* @example
*
* _.isUndefined(void 0);
* // => true
*
* _.isUndefined(null);
* // => false
*/
function isUndefined(value) {
return typeof value == 'undefined';
}
/**
* Converts `value` to an array.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to convert.
* @returns {Array} Returns the converted array.
* @example
*
* (function() { return _.toArray(arguments).slice(1); })(1, 2, 3);
* // => [2, 3]
*/
function toArray(value) {
var length = value ? value.length : 0;
if (!isLength(length)) {
return values(value);
}
if (!length) {
return [];
}
return arrayCopy(value);
}
/**
* Converts `value` to a plain object flattening inherited enumerable
* properties of `value` to own properties of the plain object.
*
* @static
* @memberOf _
* @category Lang
* @param {*} value The value to convert.
* @returns {Object} Returns the converted plain object.
* @example
*
* function Foo() {
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.assign({ 'a': 1 }, new Foo);
* // => { 'a': 1, 'b': 2 }
*
* _.assign({ 'a': 1 }, _.toPlainObject(new Foo));
* // => { 'a': 1, 'b': 2, 'c': 3 }
*/
function toPlainObject(value) {
return baseCopy(value, keysIn(value));
}
/*------------------------------------------------------------------------*/
/**
* Assigns own enumerable properties of source object(s) to the destination
* object. Subsequent sources overwrite property assignments of previous sources.
* If `customizer` is provided it is invoked to produce the assigned values.
* The `customizer` is bound to `thisArg` and invoked with five arguments;
* (objectValue, sourceValue, key, object, source).
*
* @static
* @memberOf _
* @alias extend
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @param {Function} [customizer] The function to customize assigning values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {Object} Returns `object`.
* @example
*
* _.assign({ 'user': 'barney' }, { 'age': 40 }, { 'user': 'fred' });
* // => { 'user': 'fred', 'age': 40 }
*
* // using a customizer callback
* var defaults = _.partialRight(_.assign, function(value, other) {
* return typeof value == 'undefined' ? other : value;
* });
*
* defaults({ 'user': 'barney' }, { 'age': 36 }, { 'user': 'fred' });
* // => { 'user': 'barney', 'age': 36 }
*/
var assign = createAssigner(baseAssign);
/**
* Creates an object that inherits from the given `prototype` object. If a
* `properties` object is provided its own enumerable properties are assigned
* to the created object.
*
* @static
* @memberOf _
* @category Object
* @param {Object} prototype The object to inherit from.
* @param {Object} [properties] The properties to assign to the object.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Object} Returns the new object.
* @example
*
* function Shape() {
* this.x = 0;
* this.y = 0;
* }
*
* function Circle() {
* Shape.call(this);
* }
*
* Circle.prototype = _.create(Shape.prototype, { 'constructor': Circle });
*
* var circle = new Circle;
* circle instanceof Circle;
* // => true
*
* circle instanceof Shape;
* // => true
*/
function create(prototype, properties, guard) {
var result = baseCreate(prototype);
if (guard && isIterateeCall(prototype, properties, guard)) {
properties = null;
}
return properties ? baseCopy(properties, result, keys(properties)) : result;
}
/**
* Assigns own enumerable properties of source object(s) to the destination
* object for all destination properties that resolve to `undefined`. Once a
* property is set, additional defaults of the same property are ignored.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @returns {Object} Returns `object`.
* @example
*
* _.defaults({ 'user': 'barney' }, { 'age': 36 }, { 'user': 'fred' });
* // => { 'user': 'barney', 'age': 36 }
*/
function defaults(object) {
if (object == null) {
return object;
}
var args = arrayCopy(arguments);
args.push(assignDefaults);
return assign.apply(undefined, args);
}
/**
* This method is like `_.findIndex` except that it returns the key of the
* first element `predicate` returns truthy for, instead of the element itself.
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to search.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {string|undefined} Returns the key of the matched element, else `undefined`.
* @example
*
* var users = {
* 'barney': { 'age': 36, 'active': true },
* 'fred': { 'age': 40, 'active': false },
* 'pebbles': { 'age': 1, 'active': true }
* };
*
* _.findKey(users, function(chr) { return chr.age < 40; });
* // => 'barney' (iteration order is not guaranteed)
*
* // using the "_.matches" callback shorthand
* _.findKey(users, { 'age': 1, 'active': true });
* // => 'pebbles'
*
* // using the "_.matchesProperty" callback shorthand
* _.findKey(users, 'active', false);
* // => 'fred'
*
* // using the "_.property" callback shorthand
* _.findKey(users, 'active');
* // => 'barney'
*/
function findKey(object, predicate, thisArg) {
predicate = getCallback(predicate, thisArg, 3);
return baseFind(object, predicate, baseForOwn, true);
}
/**
* This method is like `_.findKey` except that it iterates over elements of
* a collection in the opposite order.
*
* If a property name is provided for `predicate` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `predicate` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to search.
* @param {Function|Object|string} [predicate=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {string|undefined} Returns the key of the matched element, else `undefined`.
* @example
*
* var users = {
* 'barney': { 'age': 36, 'active': true },
* 'fred': { 'age': 40, 'active': false },
* 'pebbles': { 'age': 1, 'active': true }
* };
*
* _.findLastKey(users, function(chr) { return chr.age < 40; });
* // => returns `pebbles` assuming `_.findKey` returns `barney`
*
* // using the "_.matches" callback shorthand
* _.findLastKey(users, { 'age': 36, 'active': true });
* // => 'barney'
*
* // using the "_.matchesProperty" callback shorthand
* _.findLastKey(users, 'active', false);
* // => 'fred'
*
* // using the "_.property" callback shorthand
* _.findLastKey(users, 'active');
* // => 'pebbles'
*/
function findLastKey(object, predicate, thisArg) {
predicate = getCallback(predicate, thisArg, 3);
return baseFind(object, predicate, baseForOwnRight, true);
}
/**
* Iterates over own and inherited enumerable properties of an object invoking
* `iteratee` for each property. The `iteratee` is bound to `thisArg` and invoked
* with three arguments; (value, key, object). Iterator functions may exit
* iteration early by explicitly returning `false`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns `object`.
* @example
*
* function Foo() {
* this.a = 1;
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.forIn(new Foo, function(value, key) {
* console.log(key);
* });
* // => logs 'a', 'b', and 'c' (iteration order is not guaranteed)
*/
function forIn(object, iteratee, thisArg) {
if (typeof iteratee != 'function' || typeof thisArg != 'undefined') {
iteratee = bindCallback(iteratee, thisArg, 3);
}
return baseFor(object, iteratee, keysIn);
}
/**
* This method is like `_.forIn` except that it iterates over properties of
* `object` in the opposite order.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns `object`.
* @example
*
* function Foo() {
* this.a = 1;
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.forInRight(new Foo, function(value, key) {
* console.log(key);
* });
* // => logs 'c', 'b', and 'a' assuming `_.forIn ` logs 'a', 'b', and 'c'
*/
function forInRight(object, iteratee, thisArg) {
iteratee = bindCallback(iteratee, thisArg, 3);
return baseForRight(object, iteratee, keysIn);
}
/**
* Iterates over own enumerable properties of an object invoking `iteratee`
* for each property. The `iteratee` is bound to `thisArg` and invoked with
* three arguments; (value, key, object). Iterator functions may exit iteration
* early by explicitly returning `false`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns `object`.
* @example
*
* _.forOwn({ '0': 'zero', '1': 'one', 'length': 2 }, function(n, key) {
* console.log(key);
* });
* // => logs '0', '1', and 'length' (iteration order is not guaranteed)
*/
function forOwn(object, iteratee, thisArg) {
if (typeof iteratee != 'function' || typeof thisArg != 'undefined') {
iteratee = bindCallback(iteratee, thisArg, 3);
}
return baseForOwn(object, iteratee);
}
/**
* This method is like `_.forOwn` except that it iterates over properties of
* `object` in the opposite order.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns `object`.
* @example
*
* _.forOwnRight({ '0': 'zero', '1': 'one', 'length': 2 }, function(n, key) {
* console.log(key);
* });
* // => logs 'length', '1', and '0' assuming `_.forOwn` logs '0', '1', and 'length'
*/
function forOwnRight(object, iteratee, thisArg) {
iteratee = bindCallback(iteratee, thisArg, 3);
return baseForRight(object, iteratee, keys);
}
/**
* Creates an array of function property names from all enumerable properties,
* own and inherited, of `object`.
*
* @static
* @memberOf _
* @alias methods
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the new array of property names.
* @example
*
* _.functions(_);
* // => ['all', 'any', 'bind', ...]
*/
function functions(object) {
return baseFunctions(object, keysIn(object));
}
/**
* Checks if `key` exists as a direct property of `object` instead of an
* inherited property.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @param {string} key The key to check.
* @returns {boolean} Returns `true` if `key` is a direct property, else `false`.
* @example
*
* _.has({ 'a': 1, 'b': 2, 'c': 3 }, 'b');
* // => true
*/
function has(object, key) {
return object ? hasOwnProperty.call(object, key) : false;
}
/**
* Creates an object composed of the inverted keys and values of `object`.
* If `object` contains duplicate values, subsequent values overwrite property
* assignments of previous values unless `multiValue` is `true`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to invert.
* @param {boolean} [multiValue] Allow multiple values per key.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {Object} Returns the new inverted object.
* @example
*
* _.invert({ 'first': 'fred', 'second': 'barney' });
* // => { 'fred': 'first', 'barney': 'second' }
*
* // without `multiValue`
* _.invert({ 'first': 'fred', 'second': 'barney', 'third': 'fred' });
* // => { 'fred': 'third', 'barney': 'second' }
*
* // with `multiValue`
* _.invert({ 'first': 'fred', 'second': 'barney', 'third': 'fred' }, true);
* // => { 'fred': ['first', 'third'], 'barney': ['second'] }
*/
function invert(object, multiValue, guard) {
if (guard && isIterateeCall(object, multiValue, guard)) {
multiValue = null;
}
var index = -1,
props = keys(object),
length = props.length,
result = {};
while (++index < length) {
var key = props[index],
value = object[key];
if (multiValue) {
if (hasOwnProperty.call(result, value)) {
result[value].push(key);
} else {
result[value] = [key];
}
}
else {
result[value] = key;
}
}
return result;
}
/**
* Creates an array of the own enumerable property names of `object`.
*
* **Note:** Non-object values are coerced to objects. See the
* [ES spec](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.keys)
* for more details.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property names.
* @example
*
* function Foo() {
* this.a = 1;
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.keys(new Foo);
* // => ['a', 'b'] (iteration order is not guaranteed)
*
* _.keys('hi');
* // => ['0', '1']
*/
var keys = !nativeKeys ? shimKeys : function(object) {
if (object) {
var Ctor = object.constructor,
length = object.length;
}
if ((typeof Ctor == 'function' && Ctor.prototype === object) ||
(typeof object != 'function' && (length && isLength(length)))) {
return shimKeys(object);
}
return isObject(object) ? nativeKeys(object) : [];
};
/**
* Creates an array of the own and inherited enumerable property names of `object`.
*
* **Note:** Non-object values are coerced to objects.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the array of property names.
* @example
*
* function Foo() {
* this.a = 1;
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.keysIn(new Foo);
* // => ['a', 'b', 'c'] (iteration order is not guaranteed)
*/
function keysIn(object) {
if (object == null) {
return [];
}
if (!isObject(object)) {
object = Object(object);
}
var length = object.length;
length = (length && isLength(length) &&
(isArray(object) || (support.nonEnumArgs && isArguments(object))) && length) || 0;
var Ctor = object.constructor,
index = -1,
isProto = typeof Ctor == 'function' && Ctor.prototype === object,
result = Array(length),
skipIndexes = length > 0;
while (++index < length) {
result[index] = (index + '');
}
for (var key in object) {
if (!(skipIndexes && isIndex(key, length)) &&
!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) {
result.push(key);
}
}
return result;
}
/**
* Creates an object with the same keys as `object` and values generated by
* running each own enumerable property of `object` through `iteratee`. The
* iteratee function is bound to `thisArg` and invoked with three arguments;
* (value, key, object).
*
* If a property name is provided for `iteratee` the created "_.property"
* style callback returns the property value of the given element.
*
* If value is also provided for `thisArg` the created "_.matchesProperty"
* style callback returns `true` for elements that have a matching property
* value, else `false`.
*
* If an object is provided for `iteratee` the created "_.matches" style
* callback returns `true` for elements that have the properties of the given
* object, else `false`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to iterate over.
* @param {Function|Object|string} [iteratee=_.identity] The function invoked
* per iteration. If a property name or object is provided it is used to
* create a "_.property" or "_.matches" style callback respectively.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {Object} Returns the new mapped object.
* @example
*
* _.mapValues({ 'a': 1, 'b': 2, 'c': 3} , function(n) { return n * 3; });
* // => { 'a': 3, 'b': 6, 'c': 9 }
*
* var users = {
* 'fred': { 'user': 'fred', 'age': 40 },
* 'pebbles': { 'user': 'pebbles', 'age': 1 }
* };
*
* // using the "_.property" callback shorthand
* _.mapValues(users, 'age');
* // => { 'fred': 40, 'pebbles': 1 } (iteration order is not guaranteed)
*/
function mapValues(object, iteratee, thisArg) {
var result = {};
iteratee = getCallback(iteratee, thisArg, 3);
baseForOwn(object, function(value, key, object) {
result[key] = iteratee(value, key, object);
});
return result;
}
/**
* Recursively merges own enumerable properties of the source object(s), that
* don't resolve to `undefined` into the destination object. Subsequent sources
* overwrite property assignments of previous sources. If `customizer` is
* provided it is invoked to produce the merged values of the destination and
* source properties. If `customizer` returns `undefined` merging is handled
* by the method instead. The `customizer` is bound to `thisArg` and invoked
* with five arguments; (objectValue, sourceValue, key, object, source).
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @param {Function} [customizer] The function to customize merging properties.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {Object} Returns `object`.
* @example
*
* var users = {
* 'data': [{ 'user': 'barney' }, { 'user': 'fred' }]
* };
*
* var ages = {
* 'data': [{ 'age': 36 }, { 'age': 40 }]
* };
*
* _.merge(users, ages);
* // => { 'data': [{ 'user': 'barney', 'age': 36 }, { 'user': 'fred', 'age': 40 }] }
*
* // using a customizer callback
* var object = {
* 'fruits': ['apple'],
* 'vegetables': ['beet']
* };
*
* var other = {
* 'fruits': ['banana'],
* 'vegetables': ['carrot']
* };
*
* _.merge(object, other, function(a, b) {
* return _.isArray(a) ? a.concat(b) : undefined;
* });
* // => { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot'] }
*/
var merge = createAssigner(baseMerge);
/**
* The opposite of `_.pick`; this method creates an object composed of the
* own and inherited enumerable properties of `object` that are not omitted.
* Property names may be specified as individual arguments or as arrays of
* property names. If `predicate` is provided it is invoked for each property
* of `object` omitting the properties `predicate` returns truthy for. The
* predicate is bound to `thisArg` and invoked with three arguments;
* (value, key, object).
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The source object.
* @param {Function|...(string|string[])} [predicate] The function invoked per
* iteration or property names to omit, specified as individual property
* names or arrays of property names.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Object} Returns the new object.
* @example
*
* var object = { 'user': 'fred', 'age': 40 };
*
* _.omit(object, 'age');
* // => { 'user': 'fred' }
*
* _.omit(object, _.isNumber);
* // => { 'user': 'fred' }
*/
function omit(object, predicate, thisArg) {
if (object == null) {
return {};
}
if (typeof predicate != 'function') {
var props = arrayMap(baseFlatten(arguments, false, false, 1), String);
return pickByArray(object, baseDifference(keysIn(object), props));
}
predicate = bindCallback(predicate, thisArg, 3);
return pickByCallback(object, function(value, key, object) {
return !predicate(value, key, object);
});
}
/**
* Creates a two dimensional array of the key-value pairs for `object`,
* e.g. `[[key1, value1], [key2, value2]]`.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to inspect.
* @returns {Array} Returns the new array of key-value pairs.
* @example
*
* _.pairs({ 'barney': 36, 'fred': 40 });
* // => [['barney', 36], ['fred', 40]] (iteration order is not guaranteed)
*/
function pairs(object) {
var index = -1,
props = keys(object),
length = props.length,
result = Array(length);
while (++index < length) {
var key = props[index];
result[index] = [key, object[key]];
}
return result;
}
/**
* Creates an object composed of the picked `object` properties. Property
* names may be specified as individual arguments or as arrays of property
* names. If `predicate` is provided it is invoked for each property of `object`
* picking the properties `predicate` returns truthy for. The predicate is
* bound to `thisArg` and invoked with three arguments; (value, key, object).
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The source object.
* @param {Function|...(string|string[])} [predicate] The function invoked per
* iteration or property names to pick, specified as individual property
* names or arrays of property names.
* @param {*} [thisArg] The `this` binding of `predicate`.
* @returns {Object} Returns the new object.
* @example
*
* var object = { 'user': 'fred', 'age': 40 };
*
* _.pick(object, 'user');
* // => { 'user': 'fred' }
*
* _.pick(object, _.isString);
* // => { 'user': 'fred' }
*/
function pick(object, predicate, thisArg) {
if (object == null) {
return {};
}
return typeof predicate == 'function'
? pickByCallback(object, bindCallback(predicate, thisArg, 3))
: pickByArray(object, baseFlatten(arguments, false, false, 1));
}
/**
* Resolves the value of property `key` on `object`. If the value of `key` is
* a function it is invoked with the `this` binding of `object` and its result
* is returned, else the property value is returned. If the property value is
* `undefined` the `defaultValue` is used in its place.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to query.
* @param {string} key The key of the property to resolve.
* @param {*} [defaultValue] The value returned if the property value
* resolves to `undefined`.
* @returns {*} Returns the resolved value.
* @example
*
* var object = { 'user': 'fred', 'age': _.constant(40) };
*
* _.result(object, 'user');
* // => 'fred'
*
* _.result(object, 'age');
* // => 40
*
* _.result(object, 'status', 'busy');
* // => 'busy'
*
* _.result(object, 'status', _.constant('busy'));
* // => 'busy'
*/
function result(object, key, defaultValue) {
var value = object == null ? undefined : object[key];
if (typeof value == 'undefined') {
value = defaultValue;
}
return isFunction(value) ? value.call(object) : value;
}
/**
* An alternative to `_.reduce`; this method transforms `object` to a new
* `accumulator` object which is the result of running each of its own enumerable
* properties through `iteratee`, with each invocation potentially mutating
* the `accumulator` object. The `iteratee` is bound to `thisArg` and invoked
* with four arguments; (accumulator, value, key, object). Iterator functions
* may exit iteration early by explicitly returning `false`.
*
* @static
* @memberOf _
* @category Object
* @param {Array|Object} object The object to iterate over.
* @param {Function} [iteratee=_.identity] The function invoked per iteration.
* @param {*} [accumulator] The custom accumulator value.
* @param {*} [thisArg] The `this` binding of `iteratee`.
* @returns {*} Returns the accumulated value.
* @example
*
* var squares = _.transform([1, 2, 3, 4, 5, 6], function(result, n) {
* n *= n;
* if (n % 2) {
* return result.push(n) < 3;
* }
* });
* // => [1, 9, 25]
*
* var mapped = _.transform({ 'a': 1, 'b': 2, 'c': 3 }, function(result, n, key) {
* result[key] = n * 3;
* });
* // => { 'a': 3, 'b': 6, 'c': 9 }
*/
function transform(object, iteratee, accumulator, thisArg) {
var isArr = isArray(object) || isTypedArray(object);
iteratee = getCallback(iteratee, thisArg, 4);
if (accumulator == null) {
if (isArr || isObject(object)) {
var Ctor = object.constructor;
if (isArr) {
accumulator = isArray(object) ? new Ctor : [];
} else {
accumulator = baseCreate(isFunction(Ctor) && Ctor.prototype);
}
} else {
accumulator = {};
}
}
(isArr ? arrayEach : baseForOwn)(object, function(value, index, object) {
return iteratee(accumulator, value, index, object);
});
return accumulator;
}
/**
* Creates an array of the own enumerable property values of `object`.
*
* **Note:** Non-object values are coerced to objects.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to query.
* @returns {Array} Returns the array of property values.
* @example
*
* function Foo() {
* this.a = 1;
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.values(new Foo);
* // => [1, 2] (iteration order is not guaranteed)
*
* _.values('hi');
* // => ['h', 'i']
*/
function values(object) {
return baseValues(object, keys(object));
}
/**
* Creates an array of the own and inherited enumerable property values
* of `object`.
*
* **Note:** Non-object values are coerced to objects.
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The object to query.
* @returns {Array} Returns the array of property values.
* @example
*
* function Foo() {
* this.a = 1;
* this.b = 2;
* }
*
* Foo.prototype.c = 3;
*
* _.valuesIn(new Foo);
* // => [1, 2, 3] (iteration order is not guaranteed)
*/
function valuesIn(object) {
return baseValues(object, keysIn(object));
}
/*------------------------------------------------------------------------*/
/**
* Produces a random number between `min` and `max` (inclusive). If only one
* argument is provided a number between `0` and the given number is returned.
* If `floating` is `true`, or either `min` or `max` are floats, a floating-point
* number is returned instead of an integer.
*
* @static
* @memberOf _
* @category Number
* @param {number} [min=0] The minimum possible value.
* @param {number} [max=1] The maximum possible value.
* @param {boolean} [floating] Specify returning a floating-point number.
* @returns {number} Returns the random number.
* @example
*
* _.random(0, 5);
* // => an integer between 0 and 5
*
* _.random(5);
* // => also an integer between 0 and 5
*
* _.random(5, true);
* // => a floating-point number between 0 and 5
*
* _.random(1.2, 5.2);
* // => a floating-point number between 1.2 and 5.2
*/
function random(min, max, floating) {
if (floating && isIterateeCall(min, max, floating)) {
max = floating = null;
}
var noMin = min == null,
noMax = max == null;
if (floating == null) {
if (noMax && typeof min == 'boolean') {
floating = min;
min = 1;
}
else if (typeof max == 'boolean') {
floating = max;
noMax = true;
}
}
if (noMin && noMax) {
max = 1;
noMax = false;
}
min = +min || 0;
if (noMax) {
max = min;
min = 0;
} else {
max = +max || 0;
}
if (floating || min % 1 || max % 1) {
var rand = nativeRandom();
return nativeMin(min + (rand * (max - min + parseFloat('1e-' + ((rand + '').length - 1)))), max);
}
return baseRandom(min, max);
}
/*------------------------------------------------------------------------*/
/**
* Converts `string` to camel case.
* See [Wikipedia](https://en.wikipedia.org/wiki/CamelCase) for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to convert.
* @returns {string} Returns the camel cased string.
* @example
*
* _.camelCase('Foo Bar');
* // => 'fooBar'
*
* _.camelCase('--foo-bar');
* // => 'fooBar'
*
* _.camelCase('__foo_bar__');
* // => 'fooBar'
*/
var camelCase = createCompounder(function(result, word, index) {
word = word.toLowerCase();
return result + (index ? (word.charAt(0).toUpperCase() + word.slice(1)) : word);
});
/**
* Capitalizes the first character of `string`.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to capitalize.
* @returns {string} Returns the capitalized string.
* @example
*
* _.capitalize('fred');
* // => 'Fred'
*/
function capitalize(string) {
string = baseToString(string);
return string && (string.charAt(0).toUpperCase() + string.slice(1));
}
/**
* Deburrs `string` by converting latin-1 supplementary letters to basic latin letters.
* See [Wikipedia](https://en.wikipedia.org/wiki/Latin-1_Supplement_(Unicode_block)#Character_table)
* for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to deburr.
* @returns {string} Returns the deburred string.
* @example
*
* _.deburr('déjà vu');
* // => 'deja vu'
*/
function deburr(string) {
string = baseToString(string);
return string && string.replace(reLatin1, deburrLetter);
}
/**
* Checks if `string` ends with the given target string.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to search.
* @param {string} [target] The string to search for.
* @param {number} [position=string.length] The position to search from.
* @returns {boolean} Returns `true` if `string` ends with `target`, else `false`.
* @example
*
* _.endsWith('abc', 'c');
* // => true
*
* _.endsWith('abc', 'b');
* // => false
*
* _.endsWith('abc', 'b', 2);
* // => true
*/
function endsWith(string, target, position) {
string = baseToString(string);
target = (target + '');
var length = string.length;
position = (typeof position == 'undefined' ? length : nativeMin(position < 0 ? 0 : (+position || 0), length)) - target.length;
return position >= 0 && string.indexOf(target, position) == position;
}
/**
* Converts the characters "&", "<", ">", '"', "'", and '`', in `string` to
* their corresponding HTML entities.
*
* **Note:** No other characters are escaped. To escape additional characters
* use a third-party library like [_he_](https://mths.be/he).
*
* Though the ">" character is escaped for symmetry, characters like
* ">" and "/" don't require escaping in HTML and have no special meaning
* unless they're part of a tag or unquoted attribute value.
* See [Mathias Bynens's article](https://mathiasbynens.be/notes/ambiguous-ampersands)
* (under "semi-related fun fact") for more details.
*
* Backticks are escaped because in Internet Explorer < 9, they can break out
* of attribute values or HTML comments. See [#102](https://html5sec.org/#102),
* [#108](https://html5sec.org/#108), and [#133](https://html5sec.org/#133) of
* the [HTML5 Security Cheatsheet](https://html5sec.org/) for more details.
*
* When working with HTML you should always quote attribute values to reduce
* XSS vectors. See [Ryan Grove's article](http://wonko.com/post/html-escaping)
* for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to escape.
* @returns {string} Returns the escaped string.
* @example
*
* _.escape('fred, barney, & pebbles');
* // => 'fred, barney, & pebbles'
*/
function escape(string) {
// Reset `lastIndex` because in IE < 9 `String#replace` does not.
string = baseToString(string);
return (string && reHasUnescapedHtml.test(string))
? string.replace(reUnescapedHtml, escapeHtmlChar)
: string;
}
/**
* Escapes the `RegExp` special characters "\", "^", "$", ".", "|", "?", "*",
* "+", "(", ")", "[", "]", "{" and "}" in `string`.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to escape.
* @returns {string} Returns the escaped string.
* @example
*
* _.escapeRegExp('[lodash](https://lodash.com/)');
* // => '\[lodash\]\(https://lodash\.com/\)'
*/
function escapeRegExp(string) {
string = baseToString(string);
return (string && reHasRegExpChars.test(string))
? string.replace(reRegExpChars, '\\$&')
: string;
}
/**
* Converts `string` to kebab case (a.k.a. spinal case).
* See [Wikipedia](https://en.wikipedia.org/wiki/Letter_case#Special_case_styles) for
* more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to convert.
* @returns {string} Returns the kebab cased string.
* @example
*
* _.kebabCase('Foo Bar');
* // => 'foo-bar'
*
* _.kebabCase('fooBar');
* // => 'foo-bar'
*
* _.kebabCase('__foo_bar__');
* // => 'foo-bar'
*/
var kebabCase = createCompounder(function(result, word, index) {
return result + (index ? '-' : '') + word.toLowerCase();
});
/**
* Pads `string` on the left and right sides if it is shorter then the given
* padding length. The `chars` string may be truncated if the number of padding
* characters can't be evenly divided by the padding length.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to pad.
* @param {number} [length=0] The padding length.
* @param {string} [chars=' '] The string used as padding.
* @returns {string} Returns the padded string.
* @example
*
* _.pad('abc', 8);
* // => ' abc '
*
* _.pad('abc', 8, '_-');
* // => '_-abc_-_'
*
* _.pad('abc', 3);
* // => 'abc'
*/
function pad(string, length, chars) {
string = baseToString(string);
length = +length;
var strLength = string.length;
if (strLength >= length || !nativeIsFinite(length)) {
return string;
}
var mid = (length - strLength) / 2,
leftLength = floor(mid),
rightLength = ceil(mid);
chars = createPad('', rightLength, chars);
return chars.slice(0, leftLength) + string + chars;
}
/**
* Pads `string` on the left side if it is shorter then the given padding
* length. The `chars` string may be truncated if the number of padding
* characters exceeds the padding length.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to pad.
* @param {number} [length=0] The padding length.
* @param {string} [chars=' '] The string used as padding.
* @returns {string} Returns the padded string.
* @example
*
* _.padLeft('abc', 6);
* // => ' abc'
*
* _.padLeft('abc', 6, '_-');
* // => '_-_abc'
*
* _.padLeft('abc', 3);
* // => 'abc'
*/
function padLeft(string, length, chars) {
string = baseToString(string);
return string && (createPad(string, length, chars) + string);
}
/**
* Pads `string` on the right side if it is shorter then the given padding
* length. The `chars` string may be truncated if the number of padding
* characters exceeds the padding length.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to pad.
* @param {number} [length=0] The padding length.
* @param {string} [chars=' '] The string used as padding.
* @returns {string} Returns the padded string.
* @example
*
* _.padRight('abc', 6);
* // => 'abc '
*
* _.padRight('abc', 6, '_-');
* // => 'abc_-_'
*
* _.padRight('abc', 3);
* // => 'abc'
*/
function padRight(string, length, chars) {
string = baseToString(string);
return string && (string + createPad(string, length, chars));
}
/**
* Converts `string` to an integer of the specified radix. If `radix` is
* `undefined` or `0`, a `radix` of `10` is used unless `value` is a hexadecimal,
* in which case a `radix` of `16` is used.
*
* **Note:** This method aligns with the ES5 implementation of `parseInt`.
* See the [ES5 spec](https://es5.github.io/#E) for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} string The string to convert.
* @param {number} [radix] The radix to interpret `value` by.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {number} Returns the converted integer.
* @example
*
* _.parseInt('08');
* // => 8
*
* _.map(['6', '08', '10'], _.parseInt);
* // => [6, 8, 10]
*/
function parseInt(string, radix, guard) {
if (guard && isIterateeCall(string, radix, guard)) {
radix = 0;
}
return nativeParseInt(string, radix);
}
// Fallback for environments with pre-ES5 implementations.
if (nativeParseInt(whitespace + '08') != 8) {
parseInt = function(string, radix, guard) {
// Firefox < 21 and Opera < 15 follow ES3 for `parseInt`.
// Chrome fails to trim leading whitespace characters.
// See https://code.google.com/p/v8/issues/detail?id=3109 for more details.
if (guard ? isIterateeCall(string, radix, guard) : radix == null) {
radix = 0;
} else if (radix) {
radix = +radix;
}
string = trim(string);
return nativeParseInt(string, radix || (reHexPrefix.test(string) ? 16 : 10));
};
}
/**
* Repeats the given string `n` times.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to repeat.
* @param {number} [n=0] The number of times to repeat the string.
* @returns {string} Returns the repeated string.
* @example
*
* _.repeat('*', 3);
* // => '***'
*
* _.repeat('abc', 2);
* // => 'abcabc'
*
* _.repeat('abc', 0);
* // => ''
*/
function repeat(string, n) {
var result = '';
string = baseToString(string);
n = +n;
if (n < 1 || !string || !nativeIsFinite(n)) {
return result;
}
// Leverage the exponentiation by squaring algorithm for a faster repeat.
// See https://en.wikipedia.org/wiki/Exponentiation_by_squaring for more details.
do {
if (n % 2) {
result += string;
}
n = floor(n / 2);
string += string;
} while (n);
return result;
}
/**
* Converts `string` to snake case.
* See [Wikipedia](https://en.wikipedia.org/wiki/Snake_case) for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to convert.
* @returns {string} Returns the snake cased string.
* @example
*
* _.snakeCase('Foo Bar');
* // => 'foo_bar'
*
* _.snakeCase('fooBar');
* // => 'foo_bar'
*
* _.snakeCase('--foo-bar');
* // => 'foo_bar'
*/
var snakeCase = createCompounder(function(result, word, index) {
return result + (index ? '_' : '') + word.toLowerCase();
});
/**
* Converts `string` to start case.
* See [Wikipedia](https://en.wikipedia.org/wiki/Letter_case#Stylistic_or_specialised_usage)
* for more details.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to convert.
* @returns {string} Returns the start cased string.
* @example
*
* _.startCase('--foo-bar');
* // => 'Foo Bar'
*
* _.startCase('fooBar');
* // => 'Foo Bar'
*
* _.startCase('__foo_bar__');
* // => 'Foo Bar'
*/
var startCase = createCompounder(function(result, word, index) {
return result + (index ? ' ' : '') + (word.charAt(0).toUpperCase() + word.slice(1));
});
/**
* Checks if `string` starts with the given target string.
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The string to search.
* @param {string} [target] The string to search for.
* @param {number} [position=0] The position to search from.
* @returns {boolean} Returns `true` if `string` starts with `target`, else `false`.
* @example
*
* _.startsWith('abc', 'a');
* // => true
*
* _.startsWith('abc', 'b');
* // => false
*
* _.startsWith('abc', 'b', 1);
* // => true
*/
function startsWith(string, target, position) {
string = baseToString(string);
position = position == null ? 0 : nativeMin(position < 0 ? 0 : (+position || 0), string.length);
return string.lastIndexOf(target, position) == position;
}
/**
* Creates a compiled template function that can interpolate data properties
* in "interpolate" delimiters, HTML-escape interpolated data properties in
* "escape" delimiters, and execute JavaScript in "evaluate" delimiters. Data
* properties may be accessed as free variables in the template. If a setting
* object is provided it takes precedence over `_.templateSettings` values.
*
* **Note:** In the development build `_.template` utilizes sourceURLs for easier debugging.
* See the [HTML5 Rocks article on sourcemaps](http://www.html5rocks.com/en/tutorials/developertools/sourcemaps/#toc-sourceurl)
* for more details.
*
* For more information on precompiling templates see
* [lodash's custom builds documentation](https://lodash.com/custom-builds).
*
* For more information on Chrome extension sandboxes see
* [Chrome's extensions documentation](https://developer.chrome.com/extensions/sandboxingEval).
*
* @static
* @memberOf _
* @category String
* @param {string} [string=''] The template string.
* @param {Object} [options] The options object.
* @param {RegExp} [options.escape] The HTML "escape" delimiter.
* @param {RegExp} [options.evaluate] The "evaluate" delimiter.
* @param {Object} [options.imports] An object to import into the template as free variables.
* @param {RegExp} [options.interpolate] The "interpolate" delimiter.
* @param {string} [options.sourceURL] The sourceURL of the template's compiled source.
* @param {string} [options.variable] The data object variable name.
* @param- {Object} [otherOptions] Enables the legacy `options` param signature.
* @returns {Function} Returns the compiled template function.
* @example
*
* // using the "interpolate" delimiter to create a compiled template
* var compiled = _.template('hello <%= user %>!');
* compiled({ 'user': 'fred' });
* // => 'hello fred!'
*
* // using the HTML "escape" delimiter to escape data property values
* var compiled = _.template('<%- value %>');
* compiled({ 'value': '