“Nieskończone parametry JavaScript” Kod odpowiedzi

Nieskończone parametry JavaScript

Functions can access an array-like object called arguments that contains all the arguments that they received

function print_my_arguments(/**/){
    var args = arguments;
    for(var i=0; i<args.length; i++){
        console.log(args[i]);
    }
};

Some important points to note:

- arguments isn't an actual array. You can convert it to an array with the following line:
	var args = Array.prototype.slice.call(arguments);

Slice is also useful if you want your array to only contain the non-named arguments that were received:

    function foo(first_arg, second_arg /**/){
        var variadic_args = Array.prototype.slice.call(arguments, 2);
    }

Not every browser can handle an arbitrarily large number of function parameters.
Last time I tested this, in Chrome and IE there was a stackoverflow after some 200.000 arguments. 
If your function can receive an arbitrarily large number of arguments,
consider packing all of those arguments in an regular array instead.

    Those /**/ comments that appear in the arguments lists for my examples are not mandatory. They are just a coding a convention that I use to mark my variadic functions and differentiate them from regular functions.

    // A quick glance would suggest that this function receives no
    // parameters but actually it is a variadic function that gets
    // its parameters via the `arguments` object.
    function foo(){
        console.log(arguments.length);
    }