Extended Mochikit.

MochiPlus.js

var create_class = function () {
  var m = MochiKit.Base;
  var iter = MochiKit.Iter;

  var new_func = function () {
    if (typeof this._new !== 'function') {
      return;
    }
    this._new.apply(this, arguments);
  };

  iter.forEach(
    arguments,
    m.partial(m.update, new_func.prototype)
  );
      
  return new_func;
};

var Lazy = function (func) {
  var m = MochiKit.Base;
  this.func = func;
  this.arg_count = m.isUndefinedOrNull(arguments[1]) ? 0 : arguments[1];
};

var hole = {};
var lazy = function (func, arg_count) {
  return new Lazy(func, arg_count);
};

var my_partial = function (func) {
  var m = MochiKit.Base;
  var it = MochiKit.Iter;

  var base_args = m.extend(null, arguments, 1);

  return function () {
    var args = arguments;
    args.shift = Array.prototype.shift;

    var new_args = [];

    it.forEach(base_args, function (arg) {
      if (arg !== hole && !(arg instanceof Lazy)) {
        new_args.push(arg);
        return;
      }

      if (arg == hole) {
        if (!m.isUndefinedOrNull(args[0])) {
          new_args.push(args.shift());
        }
        return;
      }

      var lazy_args = [];
      for (var count = 0; count < arg.arg_count; count++) {
        if (m.isUndefinedOrNull(args[0])) {
          break;
        }
        lazy_args.push(args.shift());
      }
      new_args.push(arg.func.apply(this, lazy_args));
    });

    it.forEach(args, function (arg) {
      new_args.push(arg);
    });

    func.apply(this, new_args);
  }
}