Dear Committee, Proposal #400 "COMPLETE set signatures” by Sebastian Graf has been submitted for our consideration. Read it here: https://github.com/sgraf812/ghc-proposals/blob/constrained-complete-sigs/pro... Discussion here: https://github.com/ghc-proposals/ghc-proposals/pull/400 The proposal presents an alternative treatment for type annotations on COMPLETE pragmas. Today one could write {-# COMPLETE P, Q :: Either #-} where P and Q are some pattern synonyms. But this isn’t even well-kinded. Instead, the author proposes that we ask our users to write {-# COMPLETE P, Q :: Either l r #-} By requiring a proper type on the RHS, we also gain the ability to talk about more advanced use cases (described in the proposal). I recommend acceptance. In fact, I learned about the way these annotations are treated today only from reading the proposal, and it came as a surprise to me. Using proper, well-kinded types there, seems like the right thing to do even if we ignore the new use cases it enables. Let me know what you think. - Vlad