clone

offers foolproof deep cloning of objects, arrays, numbers, strings etc. in JavaScript.

Installation

npm install clone

(It also works with browserify, ender or standalone.)

Example

var clone = require('clone');

var a, b;

a = { foo: { bar: 'baz' } };  // initial value of a

b = clone(a);                 // clone a -> b
a.foo.bar = 'foo';            // change a

console.log(a);               // show a
console.log(b);               // show b

This will print:

{ foo: { bar: 'foo' } }
{ foo: { bar: 'baz' } }

clone masters cloning simple objects (even with custom prototype), arrays, Date objects, and RegExp objects. Everything is cloned recursively, so that you can clone dates in arrays in objects, for example.

API

clone(val, circular, depth)

val -- the value that you want to clone, any type allowed
circular -- boolean
Call clone with circular set to false if you are certain that obj contains no circular references. This will give better performance if needed. There is no error if undefined or null is passed as obj.
depth -- depth to which the object is to be cloned (optional, defaults to infinity)

clone.clonePrototype(obj)

obj -- the object that you want to clone

Does a prototype clone as described by Oran Looney.

Circular References

var a, b;

a = { hello: 'world' };

a.myself = a;
b = clone(a);

console.log(b);

This will print:

{ hello: "world", myself: [Circular] }

So, b.myself points to b, not a. Neat!

Test

npm test

Caveat

Some special objects like a socket or process.stdout/stderr are known to not be cloneable. If you find other objects that cannot be cloned, please open an issue.

Bugs and Issues

If you encounter any bugs or issues, feel free to open an issue at github or send me an email to paul@vorba.ch. I also always like to hear from you, if you’re using my code.

License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.