http://www.perlmonks.org?node_id=233859

Although there are now Devel:: modules on CPAN which do an excellent job of making symbol tables easy to play with, I wrote these three routines for quick debugging of some code which played around with Safe and other symbol table tricks.
sub packages { print "Packages: ", join(" ", grep /::$/, keys %::), "\n"; print " INC: ", join(" ", sort keys %INC), "\n"; } sub symbols { my $pkg = $_[0] || ''; no strict 'refs'; print "Symbols: ", join(" ", sort keys %{$pkg.'::'}), "\n"; } sub symbols2 { my $pkg = $_[0] || ''; no strict 'refs'; print "Symbols in ${pkg}::\n"; my $hash = *{$pkg.'::'}{HASH}; for (sort grep {!/::$|^_</} keys %$hash) { my $sym = $_; my $glob = $hash->{$_}; $sym =~ s/[[:cntrl:]]/'^' . chr(ord($&) + ord('@'))/ge; print " $sym (", *{$glob}{PACKAGE}, '::', *{$glob}{NAME}, "): "; if (defined $$_) { print "SCALAR='$$glob' "; }; for my $THING (qw(ARRAY HASH CODE IO)) { my $ref = *{$glob}{$THING}; if (defined $ref) { print "$THING=$ref "; } } print "\n"; } }