I almost never export anything from modules I write. I almost always:

use Wibble qw();
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when I use modules. I means I have to:

Wibble::Wobble();
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when I need to call Wobble(), but at least I know where Wobble() lives that way even minutes, or months, after I wrote the code.

Using OO largely avoids the name space pollution problem that these measures seek to avoid without cluttering the code with explicit name space references.