Writing a compiler in elm?

[Philipp_Krueger]

@evancz

Only technical note that stands out to me is that the type inference algorithm absolutely needs mutation to run in roughly linear time for large files. Specifically the union-find data structure as outlined here . Without it, you can get really bad asymptotics that are obvious when you start getting to 200+ line files.

If I remember correctly, our professor told us that ghc type inference works using a greedy algorithm that performs worse than union-find asymptotically, but better in practise.

I took a look at ghc source code and it seems there is a pure unification algorithm in its Unify.hs module using “Algorithm U”, and an impure unification algorithm in TcUnify.hs.

Maybe a pure unifier in elm-in-elm could perform sufficiently well?