How can I pre-set arguments in JavaScript function call? (Partial Function Application)

First of all, you need a partial - there is a difference between a partial and a curry - and here is all you need, without a framework:

function partial(func /*, 0..n args */) {
  var args = Array.prototype.slice.call(arguments, 1);
  return function() {
    var allArguments = args.concat(Array.prototype.slice.call(arguments));
    return func.apply(this, allArguments);
  };
}

Now, using your example, you can do exactly what you are after:

partial(out, "hello")("world");
partial(out, "hello", "world")();

// and here is my own extended example
var sayHelloTo = partial(out, "Hello");
sayHelloTo("World");
sayHelloTo("Alex");

The partial() function could be used to implement, but is not currying. Here is a quote from a blog post on the difference:

Where partial application takes a function and from it builds a function which takes fewer arguments, currying builds functions which take multiple arguments by composition of functions which each take a single argument.

Hope that helps.

Is curried javascript what you're looking for?

Using Javascript's apply(), you can modify the function prototype

Function.prototype.pass = function() {
    var args = arguments,
        func = this;
    return function() {
        func.apply(this, args);
    }
};

You can then call it as out.pass('hello','world')

apply takes an array for 2nd argument/parameter.

arguments is property available inside function which contains all parameters in array like structure.

One other common way to do this is to use bind

loadedFunc = func.bind(this, v1, v2, v3);

then

loadedFunc() === this.func(v1,v2,v3);

this kinda suffice, even though little ugly.