This does all the straightforward tests, and warns and returns undef on stuff it can't reliably compare (like code refs). Would probably be better to use UNIVERSAL::isa rather than ref.
sub deep_eq {
my ($a, $b) = @_;
if (not defined $a) { return not defined $b }
elsif (not defined $b) { return 0 }
elsif (not ref $a) { $a eq $b }
elsif ($a eq $b) { return 1 }
elsif (ref $a ne ref $b) { return 0 }
elsif (ref $a eq 'SCALAR') { $$a eq $$b }
elsif (ref $a eq 'ARRAY') {
if (@$a == @$b) {
for (0..$#$a) {
my $rval;
return $rval unless ($rval = deep_eq($a->[$_], $b->[$_
+]));
}
return 1;
}
else { return 0 }
}
elsif (ref $a eq 'HASH') {
if (keys %$a == keys %$b) {
for (keys %$a) {
my $rval;
return $rval unless ($rval = deep_eq($a->{$_}, $b->{$_
+}));
}
return 1;
}
else { return 0 }
}
elsif (ref $a eq ref $b) { warn 'Cannot test '.(ref $a)."\n"; un
+def }
else { return 0 }
}
