Commit 716385c9 authored by Committed by Marge Bot
Make DataKinds the sole arbiter of kind-level literals (and friends)
Previously, the use of kind-level literals, promoted tuples, and promoted lists required enabling both `DataKinds` and `PolyKinds`. This made sense back in a `TypeInType` world, but not so much now that `TypeInType`'s role has been superseded. Nowadays, `PolyKinds` only controls kind polymorphism, so let's make `DataKinds` the thing that controls the other aspects of `TypeInType`, which include literals, promoted tuples and promoted lists. There are some other things that overzealously required `PolyKinds`, which this patch fixes as well: * Previously, using constraints in kinds (e.g., `data T :: () -> Type`) required `PolyKinds`, despite the fact that this is orthogonal to kind polymorphism. This now requires `DataKinds` instead. * Previously, using kind annotations in kinds (e.g., `data T :: (Type :: Type) -> Type`) required both `KindSignatures` and `PolyKinds`. This doesn't make much sense, so it only requires `KindSignatures` now. Fixes #18831.
Showing with 54 additions and 36 deletions