in reply to Writing Modules/namespace polution

Your name space isn't poluted:

use strict; use warnings; use mymodule; print "My Test\n"; Func1(); # ERROR! Func2("Fluffy", 5); # ERROR!

But check this out:

use strict; use warnings; use mymodule qw( Func1 ); # Import Func1 #use mymodule qw( Func2 ); # This won't work since # Func2 is not in @EXPORT_OK. print "My Test\n"; Func1(); Func2("Fluffy", 5); # ERROR!

You should never export methods. As you can see, there's no reason to do so. All functions in a package are tied to the object blessed to that package, whether you use Exporter or not.

and how can I prevent it as it seems to be allowing everything into the calling script's namespace?

It's possible to disguise a function using lexicals and/or closures so that noone outside the package can call it, but there's no need to do so. Write proper documentation instead.