#!./perl -w use strict; use warnings; use Data::Dumper; use Test::More tests => 4; package Foo; use overload '""' => 'as_string'; sub new { bless { foo => "bar" }, shift } sub as_string { "%%%%" } package main; my $f = Foo->new; isa_ok($f, 'Foo'); is("$f", '%%%%', 'String overloading works'); my $d = Dumper($f); like($d, qr/bar/); like($d, qr/Foo/);