Both
Test::Differences::eq_or_diff and
Test::Deep::is_deeply want to call
Test::Builder->ok($pass_or_fail) after they do their comparison, they also output diagnostics each time. They are not suitable for use with LT as LT wants to call them 1000s of times for each call to
Test::Builder->ok.
Test::Deep::eq_deeply is different, it just returns the result, no diagnostics, no talking to the test framework, it's designed for use independently of the test framework. Test::Differences may have a similar function, I'm not sure.
