Sha256: 2cc88d3c446f208ed2bf624de9fcab99e26a122eeaf922e11fd1d3a9193a9f2c
Contents?: true
Size: 1.58 KB
Versions: 17
Compression:
Stored size: 1.58 KB
Contents
var Promise = require('native-or-bluebird')
var assert = require('assert')
module.exports = thenify
/**
* Turn async functions into promises
*
* @param {Function} $$__fn__$$
* @return {Function}
* @api public
*/
function thenify($$__fn__$$) {
assert(typeof $$__fn__$$ === 'function')
return eval(createWraper($$__fn__$$.name))
}
/**
* Turn async functions into promises and backward compatible with callback
*
* @param {Function} $$__fn__$$
* @return {Function}
* @api public
*/
thenify.withCallback = function ($$__fn__$$) {
assert(typeof $$__fn__$$ === 'function')
return eval(createWraper($$__fn__$$.name, true))
}
function createCallback(resolve, reject) {
return function(err, value) {
if (err) return reject(err)
var length = arguments.length
if (length <= 2) return resolve(value)
var values = new Array(length - 1)
for (var i = 1; i < length; ++i) values[i - 1] = arguments[i]
resolve(values)
}
}
function createWraper(name, withCallback) {
withCallback = withCallback ?
'var lastType = typeof arguments[len - 1]\n'
+ 'if (lastType === "function") return $$__fn__$$.apply(self, arguments)\n'
: ''
return '(function ' + (name || '') + '() {\n'
+ 'var self = this\n'
+ 'var len = arguments.length\n'
+ withCallback
+ 'var args = new Array(len + 1)\n'
+ 'for (var i = 0; i < len; ++i) args[i] = arguments[i]\n'
+ 'var lastIndex = i\n'
+ 'return new Promise(function (resolve, reject) {\n'
+ 'args[lastIndex] = createCallback(resolve, reject)\n'
+ '$$__fn__$$.apply(self, args)\n'
+ '})\n'
+ '})'
}
Version data entries
17 entries across 17 versions & 2 rubygems