Clones plain js hashes and arrays recursively. But ignores Dates and object Wrappers like Boolean(), Number() etc.
Tested in IE8, Chromium, Firefox, Opera and on Android.
Handles circular references (loops of the length 1).
If you want a more powerfull deepcloner (not fitting in 140 bytes though), consider using this one: https://gist.github.com/0d3e6ce689e76105f3ef
| function c(o,i,r){ // only "o" is used as an argument, r and i are used as mere local variables. "r" MUST be undefined | |
| if(o && typeof o=="object") { // clone "o" only if it is an "object" and is not null | |
| r = o instanceof Array ? [] : {}; // use "instanceof" instead of Array.isArray() to support IE8 | |
| for(i in o) | |
| o.hasOwnProperty(i)? // "condition?action:0" saves us a single byte (compare to "if(condition)action") | |
| // recursive cloning goes here: | |
| r[i] = o[i]===o ? r : c(o[i]) // if "o[i]" is "o" - we have a primitive 1-length loop. Hanlde it | |
| :0 // end of the "condition?action:0" statement | |
| } | |
| return r||o // if r was assigned to {} or [] then return r. Otherwise return the original object | |
| } // when all spaces and comments are removed this function is exactly 140 bytes! |
| function c(o,i,r){if(o&&typeof o=="object"){r=o instanceof Array?[]:{};for(i in o)o.hasOwnProperty(i)?r[i]=o[i]===o?r:c(o[i]):0}return r||o} |
| DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE | |
| Version 2, December 2004 | |
| Copyright (C) 2012 lxyd <https://github.com/lxyd>, TheShock <https://github.com/theshock> | |
| Everyone is permitted to copy and distribute verbatim or modified | |
| copies of this license document, and changing it is allowed as long | |
| as the name is changed. | |
| DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE | |
| TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION | |
| 0. You just DO WHAT THE FUCK YOU WANT TO. |
| { | |
| "name": "planeObjectDeepCloner", | |
| "description": "Recursively clones plain hashes and arrays (but not Dates or wrappers like Boolean(), String(), Number()). Handles one-level circular references.", | |
| "keywords": [ | |
| "clone", | |
| "object", | |
| "array" | |
| ] | |
| } |
| <!DOCTYPE html> | |
| <title>Deep Cloner</title> | |
| <script> | |
| function c(o,i,r){if(o&&typeof o=="object"){r=o instanceof Array?[]:{};for(i in o)o.hasOwnProperty(i)?r[i]=o[i]===o?r:c(o[i]):0}return r||o} | |
| var x = { | |
| a: [ | |
| {a:0, b:null, c:[1,2,"foo"]}, | |
| 1, | |
| null | |
| ], | |
| b: { | |
| a:{}, | |
| b:null, | |
| c:[1,2,3] | |
| } | |
| }; | |
| x.c = x; // circular reference (1-length loop) | |
| var y = c(x); | |
| document.write('Just after cloning<br/>'); | |
| document.write('x.c === x: ' + (x.c === x) + '<br/>'); | |
| document.write('y.c === y: ' + (y.c === y) + '<br/>'); | |
| document.write('x.a[0].c[2] == ' + x.a[0].c[2] + '<br/>'); | |
| document.write('y.a[0].c[2] == ' + y.a[0].c[2] + '<br/>'); | |
| x.a[0].c[2] = "bar"; | |
| document.write('<br/>After assiginig x.a[0].c[2] = "bar"<br/>'); | |
| document.write('x.a[0].c[2] == ' + x.a[0].c[2] + '<br/>'); | |
| document.write('y.a[0].c[2] == ' + y.a[0].c[2] + '<br/>'); | |
| </script> |
But what if we have a property "pop" in an Object? I don't think this is a good idea...
UPD: your variant also fails on nulls (typeof null == "object" too, so o.pop and o.hasOwnProperty will fail)
instanceof is another bad idea (though not too bad). A more secure isArray method can be found in https://gist.github.com/1034882 - but that's probably too long to use here. I would suggest the following solution, but alas, it is 16bytes too long:
function c(o,i,r){r=/[AO]/.exec({}.toString.call(o));if(r&&''+o!==o){r=r[0]=='A'?[]:{};for(i in o)o.hasOwnProperty(i)?r[i]=o[i]===o?r:c(o[i]):0}return r||o}
isArray is not too long, but it does not work in IE8 unfortunately.
Since arrays and objects are almost the same thing, would it be possible to skip the check?
Not because after cloning array I want to have an array and not an object with some integer keys :)
The difference is: adding elements won't change length, there will not be any push/pop properties etc.
That makes perfect sense!
Save some bytes by using o.pop instead of o instanceof Array (from the Byte-saving Techniques page on the wiki)