Skip to content

Validity check quantified constraints

This module is accepted:

{-# LANGUAGE QuantifiedConstraints #-}

module Bug2 where

blah :: (forall a. a b ~ a c) => b -> c
blah = undefined

But it shouldn't be: it uses ~ with neither GADTs nor TypeFamilies enabled.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information