wallet-core/node_modules/when/lib/Scheduler.js

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2016-10-10 03:43:44 +02:00
/** @license MIT License (c) copyright 2010-2014 original author or authors */
/** @author Brian Cavalier */
/** @author John Hann */
(function(define) { 'use strict';
define(function() {
// Credit to Twisol (https://github.com/Twisol) for suggesting
// this type of extensible queue + trampoline approach for next-tick conflation.
/**
* Async task scheduler
* @param {function} async function to schedule a single async function
* @constructor
*/
function Scheduler(async) {
this._async = async;
this._running = false;
this._queue = this;
this._queueLen = 0;
this._afterQueue = {};
this._afterQueueLen = 0;
var self = this;
this.drain = function() {
self._drain();
};
}
/**
* Enqueue a task
* @param {{ run:function }} task
*/
Scheduler.prototype.enqueue = function(task) {
this._queue[this._queueLen++] = task;
this.run();
};
/**
* Enqueue a task to run after the main task queue
* @param {{ run:function }} task
*/
Scheduler.prototype.afterQueue = function(task) {
this._afterQueue[this._afterQueueLen++] = task;
this.run();
};
Scheduler.prototype.run = function() {
if (!this._running) {
this._running = true;
this._async(this.drain);
}
};
/**
* Drain the handler queue entirely, and then the after queue
*/
Scheduler.prototype._drain = function() {
var i = 0;
for (; i < this._queueLen; ++i) {
this._queue[i].run();
this._queue[i] = void 0;
}
this._queueLen = 0;
this._running = false;
for (i = 0; i < this._afterQueueLen; ++i) {
this._afterQueue[i].run();
this._afterQueue[i] = void 0;
}
this._afterQueueLen = 0;
};
return Scheduler;
});
}(typeof define === 'function' && define.amd ? define : function(factory) { module.exports = factory(); }));