Package Exports

modify-event

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (modify-event) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

modify-event

Modify the value of the specific object's event

var EventEmitter = require('events').EventEmitter;
var modifyEvent = require('modify-event');

var emitter = new EventEmitter();

modifyEvent(emitter, 'foo', function(val) {
  return val * 2;
});

emitter.on('foo', function(data) {
  data; //=> 2
});

emitter.emit('foo', 1);

Installation

Use npm.

npm install modify-event

API

var modifyEvent = require('modify-event');

modifyEvent(eventEmitter, eventName, modifier)

eventEmitter: Object (an instance of EventEmitter or its inheritance e.g. Stream)
eventName: String (event name)
modifier: Function
Return: Object (Same as the first argument)

It changes the first argument of the event listeners for a given event, in response to the return value of the modifier function.

var EventEmitter = require('events').EventEmitter;
var modifyEvent = require('modify-event');

var emitter = new EventEmitter();

modifyEvent(emitter, 'data', function(val) {
  return val + 'b';
});

modifyEvent(emitter, 'data', function(val) {
  return val + 'c';
});

emitter
.on('data', listener)
.emit('data', 'a');

function listener(data) {
  data; //=> 'abc'
}

License

Licensed under the MIT License.