Dynamically give access to JavaScript functions

The title may be a bit non-descriptive, so let me explain what I want to do.

I have a lot of JavaScript functions that I want to be able to "give access to" based on a user's permissions to do certain things on my system. As an example:

I have a JS function to add an employee:

function doNewEmployee() {
    var x;
    var objTemp=new Object();
    var myElements = new Array ("username","password1", "password2", "emp_type",
 "name", "surname", "personal_contact", "work_contact", "location_dd",
 "home_address", "access_level", "id_num");
    for (x=0;x<myElements.length;x++){
        objTemp[''+myElements[x]+'']=document.getElementById(myElements[x]).value;
    }
    asyncProxy.addNewEmployee(objTemp);
}

This sends all the parameters through AJAX to my PHP

Now, what I want to be able to do is check whether the user has permissions to execute this function and only include it in the final JS file sent client-side if this is true.

Is this possible? I was thinking about just creating a load of if statements, echoing out the javascript functions in the index.php file, but this would entail having all my JS inline, which isn't what I want.

I guess at the end of the day I want a dynamically built JS file?

Any help would be greatly appreciated!