44 lines
1.2 KiB
JavaScript
44 lines
1.2 KiB
JavaScript
/**
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* @fileOverview inherit, an alternative for __proto__
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* @author YUKI "Piro" Hiroshi
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* @contributor Infocatcher
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* @version 3
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*
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* @license
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* The MIT License, Copyright (c) 2014 YUKI "Piro" Hiroshi.
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* https://github.com/piroor/fxaddonlib-inherit/blob/master/LICENSE
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* @url http://github.com/piroor/fxaddonlib-inherit
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*/
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const EXPORTED_SYMBOLS = ['inherit'];
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function toPropertyDescriptors(aProperties) {
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var descriptors = {};
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Object.keys(aProperties).forEach(function(aProperty) {
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var description = Object.getOwnPropertyDescriptor(aProperties, aProperty);
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descriptors[aProperty] = description;
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});
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return descriptors;
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}
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function inherit(aParent, aExtraProperties) {
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var global;
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if (Components.utils.getGlobalForObject)
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global = Components.utils.getGlobalForObject(aParent);
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else
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global = aParent.valueOf.call();
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global = global || this;
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var ObjectClass = global.Object || Object;
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if (!ObjectClass.create) {
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aExtraProperties = aExtraProperties || new ObjectClass;
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aExtraProperties.__proto__ = aParent;
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return aExtraProperties;
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}
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if (aExtraProperties)
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return ObjectClass.create(aParent, toPropertyDescriptors(aExtraProperties));
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else
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return ObjectClass.create(aParent);
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}
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