List of global user defined functions in JavaScript?

Question

Is it possible to get a list of the user defined functions in JavaScript?

I'm currently using this, but it returns functions which aren't user defined:

var functionNames = [];

for (var f in window) {
    if (window.hasOwnProperty(f) && typeof window[f] === 'function') {
        functionNames.push(f);
    }
}

Answer 1

I'm assuming you want to filter out native functions. In Firefox, Function.toString() returns the function body, which for native functions, will be in the form:

function addEventListener() {      [native code]  } 

You could match the pattern /\[native code\]/ in your loop and omit the functions that match.

Answer 2

As Chetan Sastry suggested in his answer, you can check for the existance of [native code] inside the stringified function:

Object.keys(window).filter(function(x) {     if (!(window[x] instanceof Function)) return false;     return !/\[native code\]/.test(window[x].toString()) ? true : false; }); 

Or simply:

Object.keys(window).filter(function(x) {     return window[x] instanceof Function && !/\[native code\]/.test(window[x].toString()); }); 

in chrome you can get all non-native variables and functions by:

Object.keys(window);