tkbjs#23

gistfile1.js

Function.prototype.method = function (name, func) {
   this.prototype[name] = func;
   return this;
};

Array.method('reduce', function(f, value) {
   var i;
   for (i = 0; i < this.length; i += 1) {
      value = f(this[i], value);
   }
   return value;
});

var data = [4, 8, 15, 16, 23, 42];

var add = function (a, b) {
   return a + b;
};

var mult = function (a, b) {
   return a * b;
};

var sum = data.reduce(add, 0);
document.writeln(sum);