is(*{::feh}{CODE}, undef, 'feh isn\'t defined');
is(*{::feh}{CODE}, undef, 'feh isn\'t defined, really');
isnt(*{::yay}{CODE}, undef, 'yay is defined');
is(*{::feh}{CODE}, undef, 'feh isn\'t defined');
is(*{::feh}{CODE}, undef, 'feh isn\'t defined, really');
isnt(*{::yay}{CODE}, undef, 'yay is defined');