Basic JavaScript classes extension

jsExtensions.js

if (!Array.prototype.last){ //last element of Array :) If you like to write better .last() then [array.length-1]
    Array.prototype.last = function(){
        return this[this.length - 1];
    };
};


if (!Array.prototype.first){ //similarly, but first element of array [0]
    Array.prototype.first = function(){
        return this[0];
    };
};

if (!Number.prototype.isOne){ //
    Array.prototype.isOne = function(){
        return this == 1;
    };
};