what do jQuery $'s mean

Question

I'm confused by the different uses of the $ in jQuery. Take for example:

$(document).ready(function($) {
  $("#nav_lat").slicknav({prependTo:"#mobile_menu"});
});

The first $ could be replaced with "jQuery" and I realize that the second $ is being passed into the anonymous function but what does it mean? And then the last $, what does that mean?

Your answer is here : http://www.authenticsociety.com/blog/JavaScript_DollarSign — mojorisinify, Feb 23 '16 at 16:05
It is just a reference to the jQuery object library itself so that you can access the properties and methods of the library. Just like Underscores uses _ to reference the library. — Korgrue, Feb 23 '16 at 16:05
I'd also like to add that you can create your own jQuery object that doesn't conflict with other libraries with: `var j = jQuery.noConflict();` — Derek Pollard, Feb 23 '16 at 16:07

Sooraj · Accepted Answer · 2016-02-23T16:08:00.003

3

The $ is just a function. It is actually an alias for the function called jQuery, so your code can be written like this with the exact same results:

jQuery(document).ready(function() {
  jQuery("#nav_lat").slicknav({prependTo:"#mobile_menu"});
});

The reason why you pass $ - as in function($) - is to avoid conflict in case where there are other libraries who use $ as the placeholder.

edited Feb 23 '16 at 16:08

answered Feb 23 '16 at 16:04

Sooraj

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No, the reason someone would pass `jQuery` is because of other libraries that use the `$` (angular, for example). – Derek Pollard Feb 23 '16 at 16:05
4

Isn't that what i have said ? – Sooraj Feb 23 '16 at 16:06
2

No, you said *The reason why **you pass $ is to avoid conflict** in case where there are other libraries who use the same placeholder.* – Derek Pollard Feb 23 '16 at 16:07
as far as i know you pass `$` not `jQuery` – Sooraj Feb 23 '16 at 16:09
2

@OliverQueen You're describing conflicts. Angular and jQuery would both expect the `$` to be available... hence conflict..? – xyhhx Feb 23 '16 at 16:12

Chris · Answer 2 · 2016-02-23T16:07:09.673

1

$ is short for JQuery. Sometimes when you are using multiple libraries you want to use JQuery instead because $ could be used by both libs.

But using only $ is faster when you know it will use the JQuery lib.

EDIT: Fun fact, you can write the ready function like this:

$(function(){
});

edited Feb 23 '16 at 16:07

answered Feb 23 '16 at 16:03

Chris

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I wouldn't call it faster but rather *alot* less typing ;) – SidOfc Feb 23 '16 at 16:07

what do jQuery $'s mean

2 Answers2