My most esteemed brethren choroba and HaukeX already nailed down your problem.

But you seem to be confused about the difference between use and require

from the docs

use Module

Imports some semantics into the current package from the named module, generally by aliasing certain subroutine or variable names into your package. It is exactly equivalent to

BEGIN { require Module; Module->import( LIST ); }

except that Module must be a bareword. ...

BEGIN happens at compile-time, if you want to use a module at run-time, you always need to call

->import

too.

It's also an FAQ, plz see

--> What's-the-difference-between-require-and-use?

and plz follow the various links embedded in this node to round up the picture.°

HTH! :)

°) well you could already have followed some of them before