rescope/src/Emitter.js

Flexible state management system based on flux architecture, stores data components & inheritable scopes

/*
 * Copyright (c)  2018 Wise Wild Web .
 *
 *  MIT 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, ARISING FROM,
 *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 *  SOFTWARE.
 *  
 * @author : Nathanael Braun
 * @contact : caipilabs@gmail.com
 */
var is = require('is');
export default class Emitter {
    _events = {};
    
    on( evt, cb ) {
        if ( !is.string(evt) && evt )
            return Object.keys(evt).forEach(k => this.on(k, evt[k]));
        
        this._events[evt] = this._events[evt] || [];
        this._events[evt].push(cb);
        
    }
    
    un( evt, cb ) {
        if ( !is.string(evt) && evt )
            return Object.keys(evt).forEach(k => this.un(k, evt[k]));
        
        if ( !this._events[evt] ) return;
        var i = this._events[evt].indexOf(cb);
        this._events[evt].splice(i, 1);
    }
    
    emit( evt, ...argz ) {
        if ( !this._events[evt] ) return;
        let lists = [...this._events[evt]];
        
        for ( var i = 0; i < lists.length; i++ )
            lists[i](...argz)
    }
    
    addListener() {
        this.on(...arguments);
    }
    
    removeListener() {
        this.un(...arguments);
    }
    
    removeAllListeners() {
        this._events = {};
    }
    
    once( evt, cb ) {
        let fn;
        this.on(evt, fn = ( ...argz ) => {
            this.un(evt, fn);
            cb(...argz)
        });
    }
    
    
}