co-events

TOC

• Co-events
  • API
  • Aliases

Co-events

API

Listeners can be anything that co supports viz. promises, thunks, generators, arrays or objects..

var events, fs, read;
events = new CoEvents;
fs = require('fs');
read = function(filename) {
  return function(cb) {
    return fs.readFile(filename, cb);
  };
};
events.on('readFile', function*(filename) {
  return callback(null, yield read(filename));
});
return events.emit('readFile', 'LICENSE');

Good old EventEmitter style functions.

var events, fs;
events = new CoEvents;
fs = require('fs');
events.on('readFile', function(filename) {
  return callback(null, fs.readFileSync(filename));
});
return events.emit('readFile', 'LICENSE');

Listener called when event emitted.

var events;
events = new CoEvents;
events.on('event', function*() {
  return callback(null);
});
return events.emit('event');

Arguments sent by emit are applied to listener.

var events;
events = new CoEvents;
events.on('wait', function*(time) {
  yield wait(time);
  return callback(null);
});
return events.emit('wait', 500);

RemoveListener can remove attached listeners.

var events, fn;
events = new CoEvents;
fn = function*() {
  return 'Hello';
};
events.on('hello', fn);
events.removeListener('hello', fn);
assert.equal(false, events.emit('hello'));
return callback(null);

Events registered using .once are removed once they are fired.

var events;
events = new CoEvents;
events.once('hello', function*() {
  return 'Hello';
});
events.emit('hello');
assert.equal(false, events.emit('hello'));
return callback(null);

Aliases

.off is an alias of .removeListener and .trigger is an alias of .emit.

var events, fn;
events = new CoEvents;
fn = function*() {
  return 'Hello';
};
events.on('hello', fn);
events.trigger('hello');
events.off('hello', fn);
assert.equal(false, events.trigger('hello'));
return callback(null);