Question

var NS = ( function ( window, document ) {
    // ... snip
    var g_debug;
    function test( value )
    {
        g_debug = value;
    }
    return {
        test: test
    }
} ( window, document ) );

Answer 1

This:

NS.test

does not call the function. That’s just a reference to the function, and the console will print the function source as the value of your console command.

When you write:

NS.test(true)

in the console, the console prints the return value from the function. Since the function has no return statement, it’s always undefined.

You should probably declare g_debug with var someplace if you haven’t.