What does function($) mean?

Question

I just started learning JavaScript. Found a statement function($) { ...} while checking out examples. Can anyone tell me what function($) means?

See javascript clouser's. Keep in mind that **java !=javascript**. — Suresh Atta, Oct 02 '13 at 13:14
http://stackoverflow.com/questions/7341265/what-does-function-mean-in-javascript — Hanky Panky, Oct 02 '13 at 13:14
`function($)` means that you are defining a function whose first argument will be bound to the identifier `$`, which is just another identifier, no special semantics. — Marko Topolnik, Oct 02 '13 at 13:15
You can see a nice example here on stackoverflow. http://stackoverflow.com/questions/2937227/what-does-function-jquery-mean This will give a good understanding of what it does. Check this out — , Oct 02 '13 at 13:19

score 2 · Accepted Answer · answered Oct 02 '13 at 13:17

2

It means "This defines a function. When it is called: create a local variable called $ and assign the value of the first argument to it."

answered Oct 02 '13 at 13:17

Quentin

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score 0 · Answer 2 · answered Oct 02 '13 at 13:19

First off: This creates a function where $ is the first argument passed to it. It could look like this potentially:

function dollar($){
    alert($);
}

dollar("hello")
//alerts "hello"

Typically this is used when you want the $ to mean jQuery.

For example:

(function($){
    //stuff where $ === jQuery
})(jQuery)

Means that jQuery will be passed into the $ variable for the scope of anything that happens in that function.

This can be useful if you have multiple libraries within the global scope that may use the $ variable, but you have a modular plugin that refers to the necessary library as that and you don't want to rewrite the whole thing.

Note: It does not always mean jQuery but in about 80% of cases it will. Otherwise it is just a convenient way to bind a library to a shorter variable within a certain scope.

What does function($) mean?

2 Answers2