Erlang's briefly mentioned at the end of the article: > There are two other languages I found with graph types: Erlang and SWI-Prolog. I don’t know either lang

Erlang's briefly mentioned at the end of the article: > There are two other languages I found with graph types: Erlang and SWI-Prolog. I don’t know either language and cannot tell when they were added; with Erlang, at least, it was before 2008. I reached out to a person on the Erlang core language committee but did not hear back.