Editing Array cloning This edit will create a new revision. Your details (optional) Name Email (won’t be displayed; might be used for Gravatar) URL Test case details Title * Published (uncheck if you want to fiddle around before making the page public) Description (in case you feel further explanation is needed)(Markdown syntax is allowed) Are you a spammer? (just answer the question) Preparation code Preparation code HTML (this will be inserted in the <body> of a valid HTML5 document in standards mode) (useful when testing DOM operations or including libraries) Include JavaScript libraries as follows: <script src="//cdn.ext/library.js"></script> Define setup for all tests (variables, functions, arrays or other objects that will be used in the tests) (runs before each clocked test loop, outside of the timed code region) (e.g. define local test variables, reset global variables, clear canvas, etc.) (see FAQ) function cloneObject(object) { var clone = new object.constructor; for (var key in object) { clone[key] = object[key]; } return clone; } function cloneArray1(array) { var clone = []; for (var i = 0; i < array.length; i++) { clone[i] = array[i]; } return clone; } function cloneArray2(array) { var clone = [], len = array.length; for (var i = 0; i < len; i++) { clone[i] = array[i]; } return clone; } function cloneArray3(array) { return array.concat(); } function cloneArray4(array) { return array.slice(); } function cloneArray5(array) { return array.slice(0); } function cloneArray6(array) { return array.filter(True); } function cloneArray7(array) { return array.map(Identity); } function cloneArray8(array) { return Array.apply([], array); } function True() { return true; } function Identity(v) { return v; } var array = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]; Define teardown for all tests (runs after each clocked test loop, outside of the timed code region) (see FAQ) Code snippets to compare Test 1 Title Async (check if this is an asynchronous test) Code cloneObject(array); Test 2 Title Async (check if this is an asynchronous test) Code cloneArray1(array); Test 3 Title Async (check if this is an asynchronous test) Code cloneArray2(array); Test 4 Title Async (check if this is an asynchronous test) Code cloneArray3(array); Test 5 Title Async (check if this is an asynchronous test) Code cloneArray4(array); Test 6 Title Async (check if this is an asynchronous test) Code cloneArray5(array); Test 7 Title Async (check if this is an asynchronous test) Code cloneArray6(array); Test 8 Title Async (check if this is an asynchronous test) Code cloneArray7(array); Test 9 Title Async (check if this is an asynchronous test) Code cloneArray8(array);