lame js String#prototype helpers

stuff.js

function User(name) {
  this.name = name;
}

User.prototype.toString = function(){
  return '<User ' + this.name + '>';
};

User.prototype.may = function(perm){
  return false;
};

function Admin(name) {
  User.call(this, name);
}

Admin.prototype.__proto__ = User.prototype;

Admin.prototype.may = function(perm){
  return true;
};

var users = [
    new User('tj')
  , new Admin('tobi')
  , new User('loki')
];

String.prototype.__defineGetter__('prop', function(){
  var self = this;
  return function(obj){
    return obj[self];
  }
});

String.prototype.call = function(){
  var self = this
    , args = arguments;
  return function(obj){
    return obj[self].apply(obj, args);
  }
};

console.log(users.map('name'.prop));
// => ['tj', 'tobi', 'loki']

console.log(users.map('toString'.call()));
// => [ '<User tj>', '<User tobi>', '<User loki>' ]

console.log(users.filter('may'.call('delete users')));
// => [ <User tobi>' ]