I agree in principle, but then what about data types with strict fields?
E.g.
data SMaybe a = SNothing | SJust !a
f :: SMaybe Bool -> ()
f SNothing = ()
Today, we'd suggest `SJust _`.
But the checker can't differentiate between evaluation done by a
pattern-match of the user vs. something
Maybe the answer should depend on whether the scrutinee has already been
forced. The new output ("We now say", below) offers up patterns that will
change the strictness behavior of the code. The old output did not.
Reading the link below, I see that, previously, there was an inconsistency with
Hi Devs,
In https://gitlab.haskell.org/ghc/ghc/-/issues/20642 we saw that GHC >=
8.10 outputs pattern match warnings a little differently than it used to.
Example from there:
{-# OPTIONS_GHC -Wincomplete-uni-patterns #-}foo :: [a] -> [a]foo [] =
[]foo xs = ys where (_, ys@(_:_)) = splitAt 0
