You might be ... notice that you're not importing the carp function into the Top::level namespace. This is nowhere NEAR definitive, but perhaps use of Exporter in package Top is called for?

Update and hopefully more definitive: "The Exporter module implements a default import method which many modules choose to inherit rather than implement their own code." (from my system's perldoc Exporter) My take is that ISA and Exporter work together.

Philosophy can be made out of anything. Or less -- Jerry A. Fodor