Make the parentheses in function calls optional

Question

Hey, I am about to rewrite the core file for my JavaScript library and I am looking for better ways of doing everything. One of these is how I make parentheses optional, for example some function calls look like this.

Spark('p').content('Hello, World');

And others like this.

Spark.browser();

So I have optional parentheses for the Spark function. Am I right in saying this would be the best way?

window.Spark = function(arg1, arg2) {
    return {
        fn: function() {
            alert('run');
        }
    };
};

for(var f in Spark())
    Spark[f] = Spark()[f];

Spark.fn();
Spark(true, false).fn();

It just seems wrong to me although it is the only method I have come up with that works.

Answer 1

You're on the right path, but be careful. As it stands, the fn function will be instantiated every time you call Spark(...), which will cause minor performance and memory usage issues.

A cleaner approach would be to use a class and store all those functions in the prototype to avoid unnecessary memory usage:

window.Spark = (function(){

  function inner(arg1, arg2) {
    this.arg1 = arg1;
    this.arg2 = arg2;
  }

  inner.prototype = {
    fn : function() { alert('run') }
  };

  function S(arg1, arg2) { return new inner(arg1, arg2) }

  var dflt = S();
  for (var f in dflt) S[f] = dflt[f];

  return S;
})();