#!/usr/bin/perl
use strict;
use warnings;
#by Abigail of perlmonks
# example usage: $0 IO::File

my $class = shift or die "need a class\n";

eval "use $class";
die $@ if $@;
   
# First, find all the classes, and the ones it inherits.
my %classes = ($class => 1);
my @classes = ($class);
   
while (@classes) {
   my $class = pop @classes;
   no strict 'refs';
   foreach my $class (@{"$class\::ISA"}) {
       next if $classes {$class} ++;
       push @classes => $class;
   }
}

# Then find the subs in those classes.
while (my $class = each %classes) {
   no strict 'refs';
   print "From class '$class':\n";
   while (my $entry = each %{"$class\::"}) {
       print "\t$entry\n" if defined &{"$class\::$entry"};
   }
}  
__END__
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