I could see one or two valid uses. The one place I've used it for production was a tied hash package. We wanted to be able to alias package vars in the hash values with vars from the caller. Retrofitting this to older code was a pain as they HAD to be package variables so we changed the alias sub to look at caller's lexicals and then the package vars.
-Lee
"To be civilized is to deny one's nature."
Update
While on the subject, I should mention a bug/feature of PadWalker. It will NOT see all lexicals visable where the subroutine is called if you have a bare block
#!/usr/bin/perl -w
use strict;
use PadWalker qw(peek_my);
my ($oa,$ob) = ("Outer One", "Outer Two");
{
my $inb = "Bare Block"; # Will not be seen by peek_my
peeper();
}
sub peeper {
my $c = peek_my(1);
print "Lexicals:\n", (map { "Found $_ with value $c->{$_}\n" } sor
+t keys %$c ),"\n";
}