"Destroying" a function in PHP 5.2x

Question

Possible Duplicate:
Removing a function at runtime in PHP

I have a script that is including different files while running. The files all contain a function with the same name. I only need the currently included to exist. Is there any way to enable dynamic file including, so it won't be causing Fatal error: Cannot redeclare function()? In another words I need to either rename or remove the previous function.

The function is declared in a classical way function fn(){;}

Answer 1

Rather than each file defining a top-level function with the same name, consider using a very simple OO structure:

Assuming you have something like this:

switch ( $some_condition )
{
    case 'normal':
    default:
        include_once 'normal_function.php';
    break;
    case 'special':
        include_once 'special_function.php';
    break;
    case 'secret':
        include_once 'secret_function.php';
    break;
}

do_the_action();

You could replace it with something like this:

switch ( $some_condition )
{
    case 'normal':
    default:
        include_once 'normal_class.php';
        $handler_object = new Normal_Class();
    break;
    case 'special':
        include_once 'special_class.php';
        $handler_object = new Special_Class();
    break;
    case 'secret':
        include_once 'secret_class.php';
        $handler_object = new Secret_Class();
    break;
}

$handler_object->do_the_action();

And then in each of the included files, instead of one function, you would define a class containing that function, like this:

class Normal_Class
{
    public function do_the_action()
    {
        // Implementation for normal case goes here 
    }
}

Not only does this solve your problem, it puts you on the road to learning other advanced/OO PHP techniques - autoloading the files so you don't have to specify include_once every time, defining hierarchies and interfaces, etc.