An event emitter that supports calling handlers both synchronously and asynchronously. It can be used to mix in event emitter functionality into an arbitrary object, or it can be used as a global event bus.

• boomerang.js v0.1.0

Adds the onSync, onAsync, off, and trigger methods to obj.

Binds callback to the object. callback will be invoked synchronously when event is triggered. If context is set, that is the context callback will be invoked in.

Binds callback to the object. callback will be invoked asynchronously when event is triggered. If context is set, that is the context callback will be invoked in.

Removes previously-bound callbacks.

Triggers previously registered callbacks for event. Additional arguments will be passed to the callbacks when invoked. Callbacks will be invoked in the order they were attached. If a callback explicitly returns false, that will stop callback execution.

var asyncEventEmitter = boomerang.mixin({}), testVal;

asyncEventEmitter.onAsync('event', callback).trigger('event', 42);

assert(testVal === undefined);
setTimeout(function() { assert(testVal === 42); }, 100);

function callback(event, val) {
  assert(event === 'event'); 
  testVal = val;
}

Tests are written using Jasmine and ran with Karma. To run Boomerang's test suite with PhantomJS, run npm test.

Found a bug? Create an issue on GitHub.

https://github.com/jharding/boomerang/issues

For transparency and insight into the release cycle, releases will be numbered with the follow format:

<major>.<minor>.<patch>

And constructed with the following guidelines:

• Breaking backwards compatibility bumps the major
• New additions without breaking backwards compatibility bumps the minor
• Bug fixes and misc changes bump the patch

For more information on semantic versioning, please visit http://semver.org/.

Copyright (c) 2013 Jake Harding
Licensed under the MIT License.