Declaring variables javascript
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I use this convention too keep track of if a variable is storing a JQuery object. So say the function getJQueryObject() returns a JQuery object and I want to store it.
ie:
var $myJQobj = getJQueryObject();
Makes it clear that $myJQobj is a JQuery object unlike ie
var myStr = "hello";
The $ as the first character in the identifier doesn't have any special meaning, you aren't invoking a method like $() , it's just a perfectly valid identifier in JavaScript. But the factthat the $ is used in JQuery makes what I was talking about before even clearer.
Is there a reason for this?
Hard to say. Maybe he came from a PHP background where $ prefixes the variables. Maybe he's a jQuery addict. Who knows? You'd have to ask him. That aside, $ is a perfectly legitimate character to use in a JavaScript variable name but as you noted, it could cause issues with jQuery. But that's why jQuery offers a noConflict() option.
$ is a valid variable character, and in PHP all variables start with it. It's possibe that that particular developer uses $ as a "flag" to mean "this is a variable". It has no special meaning.
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