How can I detect when a function is called as a jQuery callback vs. called directly?

Question

I'm using hoverIntent which, as part of its settings, will call a function. I think this is called 'referencing a function' (correct?):

var HIconfig = {
     interval: 250,
     sensitivity: 8,
     over: myFunction,
     timeout: 100,
     out: myOtherFunction
};

However, I'd like to reuse said function at times and explicitly pass in a jQuery object. So, I added that to the function.

myFunction($myObject){
}

The challenge now is to figure out when the function is being referenced by hoverIntent or being explicitly called. My thought was that I'd check to see if $(this) contained a particular DOM element:

myFunction($myObject){
     if($(this).is('li')){
       $myObject = $(this)
     };

     $myObject.doSomething...

}

But...I'm having issues. If I log out both $(this) and $myObject these are the results:

Called via hoverIntent:

$(this) = [li#Trigger-0.nav-main-tab]
$myObject = Object { originalEvent=, more...}

Called via explicitely passing an object

$(this) = [Window PT02-home-page.php#]
$myObject = [li#Trigger-0.nav-main-tab]

I can test for $(this).is('li') in the first scenario, as it's true.

I can't in the second, though, as when I try to perform the test, Firefox doesn't like it:

g.nodeName is undefined

One suggestion was to switch to 1.4.1 and try to test for the opposite via .isPlayObject:

if (jQuery.isPlainObject($myObject))...

This works just fine in Firefox. However, IE8 always returns true.

My questions:

1. Is my logic simply way off in terms of how my function gets called from hoverIntent vs. directly?

2. If not, is there a way to consistently test to see if I have explicitly passed in an object to my variable in the function?

Answer 1

I would do this totally differently. First, it's weird to have a function take a jQuery object as a parameter. Go the jQuery way and make your function into a jQuery plugin. For use in your hoverIntent configuration, you can either wrap your function in another little function, or do that with the new (1.4) jQuery.proxy() function.

Answer 2

Instead of passing an object, why not pass a simple boolean to indicate where it has been called from, for instance:

myFunction(asOption){
    if(asOption) {
        alert("called from hoverIntent");
    } else {
        alert("called from somewhere else");
    }
}

or am I completely missing the point?

Answer 3

You're making this unnecessarily complex. Just use a wrapper for the callback that passes the argument the function expects:

var HIconfig = {
     interval: 250,
     sensitivity: 8,
     // myFunction expects a jQuery object, so create one from the context
     over: function() { myFunction($(this)) },
     timeout: 100,
     out: myOtherFunction
};

...then you can skip the check inside your function altogether:

myFunction($myObject)
{
     $myObject.doSomething...
}