Asynchronous cancelable (or not) EventEmitter-like object
An EventEmitter replacement that allows the library to make events cancelable by the event handlers and allows event handlers to be synchronous or asynchronous.
npm install async-cancelable-events
var EventEmitter = require'async-cancelable-events';var util = require'util';EventEmittercallthis;utilinheritsMyEmittingObject EventEmitter;
The API is intented to be a mostly-drop-in replacement for Node.js' EventEmitter object, with a little bit of DOM Events and more asynchronicity sprinkled in.
The primary differences between the EventEmitter and async-cancelable-events are:
this.emitis a function, it is assumed to be a callback that accepts a boolean indicating whether to continue the event (
true) or cancel it (
.oncemethods try to "guess" if the provided handler is synchronous or asynchronous (based on its argument length), or can be explicitly registered as synchronous or asynchronous with
maxListenersPassedevent with the event name and listener count as arguments. The warning the official
EventEmitterprints is simply a listener for
async-cancelable-events, and can be disabled by running
this.removeAllListeners('maxListenersPassed')just after the
foo.on('bar', func1).on('baz', func2)is valid.
Copyright (C) 2012-2013 by David Ellis
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The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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