# :stopdoc:
# This module implements a memoizer for caching styleguide() invocations.
#
module Archetype::Functions::StyleguideMemoizer
private
# memoized store for components we've already computed
@components ||= {}
#
# get the token for a styleguide reference given the current state of the theme
#
# *Parameters*:
# - theme {String} the theme name
# - extensions {Array} the list of currently installed extensions
# - id {String} the component identifier
# - modifiers {Array} the list of modifiers
# - state {String} the name of the state
# *Returns*:
# - {Fixnum} whether or not the value is nil/blank
#
def self.tokenize(theme, extensions, id, modifiers, state)
return nil if extensions.nil? or id.nil?
return "#{id}::#{(modifiers.to_a.sort + extensions).join('$')}::#{state}"
end
#
# add a value to the memoizer given a token
#
# *Parameters*:
# - theme {String} the theme name
# - token {Fixnum} the token to register
# - value {Hash} the value to store
#
def self.add(theme, token, value)
(@components[theme] ||= {})[token] = value if Compass.configuration.memoize
end
#
# fetch a value from the memoizer given a token
#
# *Parameters*:
# - theme {String} the theme name
# - token {Fixnum} the token to lookup
# *Returns*:
# - value {Hash} the value from the memoizer
#
def self.fetch(theme, token)
return false if token.nil?
return (@components[theme] ||= {})[token]
end
#
# fetch a value from the memoizer if available, otherwise execute the block and create it
#
# *Parameters*:
# - theme {String} the theme name
# - token {Fixnum} the token to lookup
# *Returns*:
# - value {Hash} the value from the memoizer
#
def self.fetch_or_create(theme, token)
fetched = self.fetch(theme, token)
return fetched if fetched
fetched = yield if block_given?
self.add(theme, token, fetched)
return fetched
end
#
# invalidate the memoizer for the theme
#
# *Parameters*:
# - theme {String} the theme name
#
def self.clear(theme)
@components[theme] = {}
end
#
# resets the entire memoizer
#
def self.reset!
@components = {}
end
end