Javascript in arguments with overload introduction

Because of a design error in the language, arguments can be treated as an array.

function zero () {

    console.log(arguments[0]);

}

There will be

function zero () {

  for(var i=0;i<arguments.length;i++){

     console.log(arguments[i]);

  }

}

It makes use of one fact of Javascript, Javasc

The arguments variable here provides an arrow-like interface to the argument. Because of the variable parameters of arguments here, we can use this interesting thing to do something interesting, like overloading.

Javscript overloading

There is a question about overloading on stackvoerflow, so you have the first answer

if (typeof friend === "undefined") {
} else {
}

And one answer is

switch (arguments.length) {

case 0:

    //Probably error

    break;

case 1:

    //Do something

    break;

case 2:

default: //Fall through to handle case of more parameters

    //Do something else

    break;

}

It's just not a nice way to do it. Is our function going to end up looking like this?

function zero1 (){

    console.log('arguments 1')

};

function zero2 (){

    console.log('arguments 2')

};

function zero () {

  if(arguments.length == 1){

    zero1();

  } else{

    zero2();

  }

}

It really doesn't look good at 1, even if we change it to switch.. case, that's not good either.

Javascript arguments is not an array

arguments is not an array as we saw 1 is an array, sometimes it might not be.

function hello(){ 

    console.log(typeof arguments);

}

Here arguments is of type 1 object, although the array is also of type 1 object, although we can convert it to an array

var args = Array.prototype.slice.call(arguments);

But this also shows that this is not an array, it has only 11 properties of Array, length. And there were

arguments.callee

Reference to the currently executing function.

arguments.caller

Reference to the function that invoked the currently executing function.

arguments.length

Reference to the number of arguments passed to the function.