When you attempt to call the method, @ISA has not yet been assigned. You could put that line in a BEGIN{}, or have it in a separate file.

Incidentally you messed up the my $class = ref($proto) || $proto meme. Which there are some good reasons not to use, it is better to make the method start with my $class = shift;

A random style note. As is pointed out in Code Complete, while many different indentation/brace styles are pretty much equivalent (as long as you are consistent), there is experimental evidence indicating that comprehension is best with indents in the 2-4 range. An indent of 6 or 8 may look more attractive, but is harder to work with. Therefore I'd strongly suggest reducing how much you indent.

In reply to Re: Revisiting strict and @ISA by tilly
in thread Revisiting strict and @ISA by Zen Seeker

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