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Comment by rdtsc | Hacker News Reader

> There’s a gap between how often software engineers could use graphs and how little our programming ecosystems support them. Where are all the graph types?

They've been there for quite a while :-) https://www.erlang.org/doc/man/digraph.html https://www.erlang.org/doc/man/digraph_utils

And if you want to do some set theoretical stuff you're covered as well: https://www.erlang.org/doc/man/sofs.html

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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.

Oh I did miss that. Thanks for pointing it out.

Elixir has a pretty nice graph library as well: https://hexdocs.pm/libgraph/api-reference.html

I've used it to do some dependency resolution for operation ordering.

Thanks for sharing. That looks well done. It has some pathfinding algorithms and the reducer is very neat for traversing the graph. I like that it's based on maps, which could make it more performant than the ets based erlang digraph.

How flexible and performant is that in different situations?

I had never used it, aside from a simple dependency checker. But I know the compiler and the Erlang types analyzer (dialyzer) uses them.

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