removeEventListener on anonymous functions in JavaScript

if you are inside the actual function, you can use arguments.callee as a reference to the function. as in:

button.addEventListener('click', function() {
      ///this will execute only once
      alert('only once!');
      this.removeEventListener('click', arguments.callee);
});

EDIT: This will not work if you are working in strict mode ("use strict";)

I believe that is the point of an anonymous function, it lacks a name or a way to reference it.

If I were you I would just create a named function, or put it in a variable so you have a reference to it.

var t = {};
var handler = function(e) {
    t.scroll = function(x, y) {
        window.scrollBy(x, y);
    };
    t.scrollTo = function(x, y) {
        window.scrollTo(x, y);
    };
};
window.document.addEventListener("keydown", handler);

You can then remove it by

window.document.removeEventListener("keydown", handler);   

A version of Otto Nascarella's solution that works in strict mode is:

button.addEventListener('click', function handler() {
      ///this will execute only once
      alert('only once!');
      this.removeEventListener('click', handler);
});