If this instance is an Optional<CharSequence> , passing an Optional<StringBuilder> will fail to compile.
Regards, Michael On 31 Oct 2015 11:21, "Stefan Zobel" <splitera...@gmail.com> wrote: > 2015-10-31 19:11 GMT+01:00 Remi Forax <fo...@univ-mlv.fr>: > > > Hi all, hi Paul, > > > > I've just seen that Optional.or is declared as > > public Optional<T> or(Supplier<Optional<T>> supplier) { > > instead of > > public Optional<T> or(Supplier<? extends Optional<T>> supplier) { > > > > regards, > > Rémi > > > > > I don't get it. Optional is final anyway. Can you explain? > > Thanks, > Stefan >