ES6-Map

ES6-Map.coffee

#https://developer.mozilla.org/en-US/docs/JavaScript/ECMAScript_6_support_in_Mozilla
Map = Map || do ->
    id = 0
    keyToObj = {}
    keyToValue = {}
    unique = ->
        "Map_#{id++}"
    getKeyByObj = (obj)->
        for own key, value of keyToObj
            if obj is value
                foundKey = key
        foundKey
    class Map
        constructor:->
        get:(obj)->
            foundKey = getKeyByObj obj
            if not not foundKey
                keyToValue[foundKey]
        set:(obj, value)->
            foundKey = getKeyByObj obj
            if not not obj
                foundKey = unique() unless foundKey
                keyToObj[foundKey] = obj
                keyToValue[foundKey] = value
            return
        delete:(obj)->
            foundKey = getKeyByObj obj
            if not not foundKey
                delete keyToObj[foundKey]
                delete keyToValue[foundKey]
        size:->
            size = 0
            for own key, value of keyToObj
                if not not value
                    size++
            size
    Map
    
map = new Map()
console.log map
console.log map.get document
map.set document, "document"
console.log map.get document
console.log map.size()
map.set document, "doc"
console.log map.get document
console.log map.size()
debugger
map.delete document
console.log map.get document
console.log map.size()