class Birch is Tree { has $.bark;

    submethod BUILD (Str $bark) {
        $.bark = $bark;
    }
}

my $birch; lives_ok { $birch = Birch.new( :bark("thick"), :node("test") ); } '... created the Tree subclass correctly';

isa_ok($birch, "Birch", "New birch"); is($birch.bark, "thick", "looks like a birch!"); is($birch.node, "test", "looks like a tree!");

ok($birch.isa(Tree), "New birch is a tree");

lives_ok { $birch.add_child(Birch.new( :bark("thin"), :node("foo"))); } '... added the child subclass okay';

my @found;

my $child; lives_ok { $child = $birch.get_child(0); } '... fetching the child';

is($child.bark, "thin", "looks like a tree!"); is($child.node, "foo", "looks like a tree!");

# bug - can't match return context to method #is($birch.get_child(0).node, "foo", "looks like a tree!");

# doesn't work - see t/oo/inheritance.t #is($birch.get_child(0).bark, "thin", "looks like a Birch!");