77 lines
1.6 KiB
JavaScript
77 lines
1.6 KiB
JavaScript
/**
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* Provides system for code reuse via traits
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*
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* Copyright (C) 2014 Mike Gerwitz
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*
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* This file is part of GNU ease.js.
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*
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* ease.js is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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function Trait()
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{
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switch ( arguments.length )
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{
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case 1:
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return Trait.extend.apply( this, arguments );
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break;
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}
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};
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Trait.extend = function( dfn )
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{
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function TraitType()
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{
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throw Error( "Cannot instantiate trait" );
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};
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TraitType.__trait = true;
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TraitType.__dfn = dfn;
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return TraitType;
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};
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Trait.isTrait = function( trait )
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{
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return !!( trait || {} ).__trait;
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};
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/**
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* Mix trait into the given definition
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*
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* The original object DFN is modified; it is not cloned.
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*
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* @param {Trait} trait trait to mix in
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* @param {Object} dfn definition object to merge into
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*
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* @return {Object} dfn
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*/
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Trait.mixin = function( trait, dfn )
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{
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var tdfn = trait.__dfn || {};
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for ( var f in tdfn )
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{
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dfn[ f ] = tdfn[ f ];
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}
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return dfn;
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};
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module.exports = Trait;
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