Implementation of the super keyword in Javascript

// We can't use super because it's apparently reserved in some JS implementations.

var superf = function(){};

function overload(object, methodName, callback){
  var superMethod = object[methodName];
  object[methodName] = function(){
    var _superf = superf;
    var me = this;
    superf = function(){
      return superMethod.apply(me, arguments);
    }
    var result = callback.apply(this, arguments);
    superf = _superf;
    return result;
  };
}

a = {"m":function(a,b){return a+b;}};

print(a.m(1,2)); // 3

overload(a, "m", function(a,b){
  return superf(a*10, b);
});

print(a.m(1,2)); // 12