Homework 2 from Mastering JS Class

Homework2.js

Math.sin = (function(){
	var original_sin = Math.sin;
	var cache = {};
	return function(n){
		if(cache[n] == null){
			cache[n] = original_sin(n);
			console.log('adding sin of ' + n.toString() + ' to cache');
		} else {
			console.log('sin cache hit: ' + n.toString());
		}
		return cache[n];
	}
})();

Function.prototype.cacher = function(){
    var original_fn = this;
    var cache = {};
	return function(n){
		if(cache[n] == null){
			cache[n] = original_fn(n);
			console.log('cacher adding ' + n.toString() + ' to cache');
		} else {
			console.log('cacher hit: ' + n.toString());
		}
		return cache[n];
	}
}


// tests
var obj = Math.sin(3);
var obj2 = Math.sin(3);
var obj3 = Math.sin(3);
var obj4 = Math.sin(4);
var obj5 = Math.sin(5);
var obj6 = Math.sin(5);

var atan = Math.tan.cacher();
var obj1 = atan(3);
var obj2 = atan(3);
var obj3 = atan(3);
var obj4 = atan(4);
var obj5 = atan(5);
var obj6 = atan(3);