Torsten Schmits authored Feb 08, 2023 and Marge Bot committed Mar 01, 2024

This implements Proposal 0475, introducing the `ListTuplePuns` extension
which is enabled by default.

Disabling this extension makes it invalid to refer to list, tuple and
sum type constructors by using built-in syntax like `[Int]`,
`(Int, Int)`, `(# Int#, Int# #)` or `(# Int | Int #)`.
Instead, this syntax exclusively denotes data constructors for use with
`DataKinds`.
The conventional way of referring to these data constructors by
prefixing them with a single quote (`'(Int, Int)`) is now a parser
error.

Tuple declarations have been moved to `GHC.Tuple.Prim` and the `Solo`
data constructor has been renamed to `MkSolo` (in a previous commit).
Unboxed tuples and sums now have real source declarations in `GHC.Types`.
Unit and solo types for tuples are now called `Unit`, `Unit#`, `Solo`
and `Solo#`.
Constraint tuples now have the unambiguous type constructors `CTuple<n>`
as well as `CUnit` and `CSolo`, defined in `GHC.Classes` like before.

A new parser construct has been ...