http://www.perlmonks.org?node_id=1214222


in reply to Re^7: Can I check if a loop's scope is entered for the first time? (Devel::Callsite)
in thread Can I check if a loop's scope is entered for the first time?

No question. It would definitely be better.

Unfortunately, there's no way to give each_value() a prototype
that allows it to also take a thunky block as an argument...in addition
to all the other argument types (hash, array, reference) it currently takes.

The current declaration is:

sub each_value (+) {...}

but, to be able to accept a block it would require:

sub each_value (&) {...}

and there's no prototype marker than allows both. :-(

Damian