Overriding Function Type prototypes

Question

I have come across an interesting behavior when playing around and trying to override Function prototype.

Let\'s assume we have overriden toString() lik

Answer 1

This is a problem of a missing semicolon:

Function.prototype.toString = function() { 
    …
}; /*
 ^ */
(function foo(){}).toString();

Otherwise it is interpreted as

Function.prototype.toString = function(){…}(function foo(){}).toString();

which calls the function expression that is supposed to override toString like an IIFE

… (function(){…}(function foo(){})) …

…in the global context, not on a function.