Adapt to NuMatchingAny1 becoming a quantified constraint
#1774
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This makes the necessary changes to adapt to eddywestbrook/hobbits#8, which turns `NuMatchingAny1` into an alias for a quantified `NuMatching` constraint. See #1742 and https://gitlab.haskell.org/ghc/ghc/-/issues/22492 for the motivation behind this. One unfortunate hiccup with this patch is that combining quantified superclasses and `TypeFamilies` doesn't quite work out of the box on pre-9.2 GHCs due to https://gitlab.haskell.org/ghc/ghc/-/issues/14860. As a result, I have to introduce explicit equality constraints to work around the issue. I have added a `Note [QuantifiedConstraints + TypeFamilies trick]` to describe why the workaround is necessary. Credit goes to Matthew Pickering for helping me identify this issue and for authoring a separate fix. I have tweaked his fix and turned it into this patch, adding him as a co-author in the process. Fixes #1742. Co-authored-by: Matthew Pickering <matthewtpickering@gmail.com>
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This makes the necessary changes to adapt to eddywestbrook/hobbits#8, which turns
NuMatchingAny1into an alias for a quantifiedNuMatchingconstraint. See #1742 and https://gitlab.haskell.org/ghc/ghc/-/issues/22492 for the motivation behind this.One unfortunate hiccup with this patch is that combining quantified superclasses and
TypeFamiliesdoesn't quite work out of the box on pre-9.2 GHCs due to https://gitlab.haskell.org/ghc/ghc/-/issues/14860. As a result, I have to introduce explicit equality constraints to work around the issue. I have added aNote [QuantifiedConstraints + TypeFamilies trick]to describe why the workaround is necessary.Credit goes to Matthew Pickering for helping me identify this issue and for authoring a separate fix. I have tweaked his fix and turned it into this patch, adding him as a co-author in the process.
Fixes #1742.