Javascript Array filterArrayLength(callback)

var names = ["Lars", "Jan", "Peter", "Bo", "Frederik"];

//Filter Prototype
Array.prototype.filterArrayLength = function(callback) {
    var newArray = [];
    for(var i = 0; i < this.length; i++) {
        if(callback(this[i]))
            newArray.push(this[i]);//from   w w  w  .  j  a  va  2 s.c  o  m
    }
    return newArray;
};

var filterArray = names.filterArrayLength(function(name){
    return name.length <= 3;
});

console.log("Filter Prototype: " + filterArray);