suppress.js

/*
© 2010 Isaac Z. Schlueter
Licensed under DWTFPL - No Rights Reserved
Please don't hurt yourself.
*/

var EE = require("events").EventEmitter
  , ee = EE.prototype
  , SE = SuppressibleEmitter
  , se = SE.prototype
  , sys = require("sys")

exports.SuppressibleEmitter = SE
exports.makeSuppressible = function (e) {
  if (e instanceof SE) return
  if (!(e instanceof EE)) throw new Error(
    "Can only make EventEmitters suppressible, not other kinds of things")
  e.__proto__ = se
  SE.call(this)
}

function SuppressibleEmitter () {
  EE.apply(this)
  this._suppressed = {}
}

sys.inherits(SE, EE)

se.suppress = function (ev) {
  this._suppressed[ev] = true
  // more fanciness here for buffering, suppressOnce, etc.
}

se.unsupress = function (ev) {
  delete this._suppressed[ev]
  // add fanciness for buffering, etc.
}

se.emit = function (ev) {
  if (this._suppressed && this._suppressed[ev]) {
    // add fanciness for buffering, suppressOnce, etc.
    return
  }
  // kludge because Function#apply is slow
  // todo: benchmark to see if it's worth it.
  return ee.emit.apply(this, arguments)
}