treestyletab/modules/lib/inherit.jsm
2014-04-02 19:25:51 +09:00

33 lines
906 B
JavaScript

/**
* @fileOverview inherit, an alternative for __proto__
* @author YUKI "Piro" Hiroshi
* @version 1
*
* @license
* The MIT License, Copyright (c) 2014 YUKI "Piro" Hiroshi.
* https://github.com/piroor/fxaddonlib-inherit/blob/master/LICENSE
* @url http://github.com/piroor/fxaddonlib-inherit
*/
const EXPORTED_SYMBOLS = ['inherit'];
function toPropertyDescriptors(aProperties) {
var descriptors = {};
Object.keys(aProperties).forEach(function(aProperty) {
var description = Object.getOwnPropertyDescriptor(aProperties, aProperty);
descriptors[aProperty] = description;
});
return descriptors;
}
function inherit(aParent, aExtraProperties) {
if (!Object.create) {
aExtraProperties.__proto__ = aParent;
return aExtraProperties;
}
if (aExtraProperties)
return Object.create(aParent, toPropertyDescriptors(aExtraProperties));
else
return Object.create(aParent);
}