$(document).ready(function() versus $(document).ready(function($)

Question

I've been working with Iphone 6 and 6S and found that the first way only work on the 6S while the second way works on both. (both use IOS 9.2.1) could someone explain the difference between:

$(document).ready(function()

and

$(document).ready(function($)

• dnapierata: Both are being executed on the document 'ready' event but the second one is being passed $ (usually jQuery) as an argument.
• AtheistP3ace: Be interested to see the closure of those. Just looks like your passing a variable in to an anonymous function on the second one.
• DCR: $(document).ready(function() { $("#nav_lat").slicknav({prependTo:"#mobile_menu"}); }); $(function($) { $("#nav_lat").slicknav({prependTo:"#mobile_menu"}); })
• spender: I find it somewhat unlikely that such a difference would cause non-operation on specific iphone models. Are you sure that there aren't other differences at play here?
• DCR: yes! have been testing this for 3 days. I think something is happening to the namespace

Answer 1

$(document).ready(function() {
 console.assert(jQuery == arguments[0] , 'my first param is jquery object')
 console.assert(this == document , 'my this is document')
 
})

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

There is no difference except naming first parameter, try:

 $(document).ready(function($) {
 console.log(arguments)

and

 $(document).ready(function() {
 console.log(arguments)
 })

Javascript does not have method overload based on parameters.

UPDATE: regardless of what definition of anonymous (or named function for that sake) you are passing , jquery will call your function as:

 func.apply(document, jquery)

See source: https://github.com/jquery/jquery/blob/99e8ff1baa7ae341e94bb89c3e84570c7c3ad9ea/src/callbacks.js#L80

So your first argument, wether you name it $ or not going to be jquery object, and your this going to be document

• DCR: everyone says this but it does not work on a Iphone 6 but does work on a Iphone 6S
• vittore: most likely it is something else, show your full code that demonstrate that behavior.