source: Dev/trunk/src/client/dojox/lang/functional/object.js

define(["dojo/_base/kernel", "dojo/_base/lang", "./lambda"], function(kernel, lang, df){

// This module adds high-level functions and related constructs:
//      - object/dictionary helpers

// Defined methods:
//      - take any valid lambda argument as the functional argument
//      - skip all attributes that are present in the empty object
//              (IE and/or 3rd-party libraries).

        var empty = {};

        lang.mixin(df, {
                // object helpers
                keys: function(/*Object*/ obj){
                        // summary:
                        //              returns an array of all keys in the object
                        var t = [];
                        for(var i in obj){
                                if(!(i in empty)){
                                        t.push(i);
                                }
                        }
                        return  t; // Array
                },
                values: function(/*Object*/ obj){
                        // summary:
                        //              returns an array of all values in the object
                        var t = [];
                        for(var i in obj){
                                if(!(i in empty)){
                                        t.push(obj[i]);
                                }
                        }
                        return  t; // Array
                },
                filterIn: function(/*Object*/ obj, /*Function|String|Array*/ f, /*Object?*/ o){
                        // summary:
                        //              creates new object with all attributes that pass the test
                        //              implemented by the provided function.
                        o = o || kernel.global; f = df.lambda(f);
                        var t = {}, v, i;
                        for(i in obj){
                                if(!(i in empty)){
                                        v = obj[i];
                                        if(f.call(o, v, i, obj)){ t[i] = v; }
                                }
                        }
                        return t;       // Object
                },
                forIn: function(/*Object*/ obj, /*Function|String|Array*/ f, /*Object?*/ o){
                        // summary:
                        //              iterates over all object attributes.
                        o = o || kernel.global; f = df.lambda(f);
                        for(var i in obj){
                                if(!(i in empty)){
                                        f.call(o, obj[i], i, obj);
                                }
                        }
                        return o;       // Object
                },
                mapIn: function(/*Object*/ obj, /*Function|String|Array*/ f, /*Object?*/ o){
                        // summary:
                        //              creates new object with the results of calling
                        //              a provided function on every attribute in this object.
                        o = o || kernel.global; f = df.lambda(f);
                        var t = {}, i;
                        for(i in obj){
                                if(!(i in empty)){
                                        t[i] = f.call(o, obj[i], i, obj);
                                }
                        }
                        return t;       // Object
                }
        });
        
        return df;
});