yatem

Yet Another Tiny Event Emitter

Install

Node

npm install yatem --save

Browser

<script src="node_modules/yatem/lib/yatem.min.js"></script>

Usage

Node

var yatem = require('yatem');
 
var e1 = yatem.on('my-event1', function () {
    console.log('This is event: my-event1');
});
var e2 = yatem.on('my-event1', function (args) {
  console.log('This is also event: my-event1, and args is: ', args);
});
var e3 = yatem.once('my-event3', function () {
    console.log('This is event: my-event3');
});
 
yatem.emit('my-event1', 'hello, world');
// output:
// > This is event: my-event1
// > This is also event: my-event1, and args is: hello, world
 
yatem.off(e2);
yatem.emit('my-event1'); // or yatem.emit(e1)
// output:
// > This is event: my-event1
 
yatem.emit('my-event3');
// output:
// > This is event: my-event3
 
yatem.emit('my-event3'); // again, it will do nothing

Browser

yatem.on('my-event', function () {
    console.log('This is event: my-event');
});
 
yatem.emit('my-event');
// output:
// > This is event: my-event

Instance Methods

on(event, callback[, context])

Subscribe to an event

• event - the name of the event to subscribe
• callback - the function to call when event is emitted
• context - (OPTIONAL) - the context to bind the event callback

If subscribe successful, return an object, that can use for yatem.off() and yatem.emit(). Otherwise return false.

var e1 = yatem.once('my-event', callback);	// typeof e1 === 'object'
var e2 = yatem.on('my-event', callback);	// e2 === false
 
yatem.emit(e1); // Ok
yatem.emit(e2); // Do nothing

once(event, callback[, context])

Subscribe to an event only once

• event - the name of the event to subscribe
• callback - the function to call when event is emitted
• context - (OPTIONAL) - the context to bind the event callback

If subscribe successful, return an object, that can use for yatem.off() and yatem.emit(). Otherwise return false.

off(event)

Unsubscribe from an event.

• event - the name of the event to unsubscribe or value that return from yate.on() or yate.once()

If event is null or undefined, and not boolean type, it will unsubscribe all events.

var e1 = yatem.on('my-event', callback1);
var e2 = yatem.on('my-event', callback2);
 
yatem.off(); // Unsubscribe all events, or use yatem.off(null)
// Notice: yatem.off(false) WILL NOT unsubscribe all events, it will do nothing
 
yatem.emit(e1); // Do nothing
yatem.emit(e2); // Do nothing

emit(event[, arguments...])

Trigger a named event or all events

• event - the event name to emit
• arguments... - any number of arguments to pass to the event subscribers

If event is null or undefined, and not boolean type, it will emit all events.

var e1 = yatem.on('my-event', callback1);
var e2 = yatem.on('my-event', callback2);
 
yatem.emit(); // Emit all events, or use yatem.emit(null[, arguments...])
// Notice: yatem.emit(false) WILL NOT emit any events, it will do nothing

Test

npm install
npm test

License

GPL-3.0