JavaScript AOP proof of concept

gistfile1.js

//AOP powers rely on invoke() being used instead of ()
Function.prototype.invoke = function(args) {
	if (this.before) {
		this.before(args);
	}
	val = this(args);
	if (this.after) {
		this.after(args);
	}
	return val;
}

Function.prototype.before = function(fn) {
	this.before = fn;
}

Function.prototype.after = function(fn) {
	this.after = fn;
}

Math.sin.before(function(arg){
	console.log('before with ' + arg.toString());
});

Math.sin.after(function(arg){
	console.log('after with ' + arg.toString());
});

Math.sin.invoke(1)
//before with 1
//after with 1
//0.8414709848078965