cloning an object (v14)

Revision 14 of this benchmark created by Oriol.tf on

Description

There is no quick and easy facility for cloning an object, Some people recommend using JQuery.extend others JSON.parse/stringify

http://stackoverflow.com/questions/122102/what-is-the-most-efficient-way-to-clone-a-javascript-object

If you want the fastest possible clone function. I would personally anticipate the data structure of your object and write a custom clone to handle it.

Preparation HTML

<script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script src="//cdnjs.cloudflare.com/ajax/libs/lodash.js/2.4.1/lodash.min.js"></script>

Setup

var oldObject = {
                a: 1,
                b: 2,
                c: 3,
                d: 4,
                e: 5,
                f: function() {
                        'use strict';
                        return 6;
                },
                g: [7, 8, 9]
        },
    
        oldArray = [
                1, 2, 3, 4, 5,
                function() {
                        'use strict';
                        return 6;
                }, 
                [7, 8, 9]
        ];
    
        clone = function(source) {
                'use strict';
                var copy, i;
                if (Object.prototype.toString.call(source) === '[object Array]') {
                        copy = [];
                        for (i=0; i<source.length; i++) {
                                copy[i] = clone(source[i]);
                        }
                        return copy;
                } else if (typeof(source) === 'object') {
                        copy = {};
                        for (var prop in source) {
                                if (source.hasOwnProperty(prop)) {
                                        copy[prop] = clone(source[prop]);
                                }
                        }
                        return copy;
                } else {
                        return source;
                }
        };

Test runner

Ready to run.

Testing in
TestOps/sec
clone(obj)
var newObject = clone(oldObject);
ready
$.extend(obj) deep
var newObject = jQuery.extend(true, {}, oldObject);
ready
loDash(obj) deep
var newObject = _.clone(oldObject, true);
ready

Revisions

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