meh

var baseclass = {
    basemethod: function() {
        return this.val + 1;
    },
}

var extendingclass = function(arg) {
    this.val = arg;
};

extendingclass.prototype = baseclass;

var secondExtendingClassThatDoesKindaTheSameThingAsTheFirstButWithDifferentValues = function(arg) {
    this.val = arg;
};

secondExtendingClassThatDoesKindaTheSameThingAsTheFirstButWithDifferentValues.prototype = baseclass;