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-- Same as T13233, but we compile with -fprint-typechecker-elaboration.
-- The error message should show an eta-expanded call to (#,#).
-- See comments at https://gitlab.haskell.org/ghc/ghc/merge_requests/2540
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE PolyKinds #-}
{-# LANGUAGE UnboxedTuples #-}
{-# LANGUAGE RankNTypes #-}
{-# LANGUAGE MagicHash #-}
module Bug where
import GHC.Exts (TYPE, RuntimeRep, Weak#, State#, RealWorld, mkWeak# )
class Foo (a :: TYPE rep) where
bar :: forall rep2 (b :: TYPE rep2). (a -> a -> b) -> a -> a -> b
baz :: forall rep (a :: TYPE rep). Foo a => a -> a -> (# a, a #)
baz = bar (#,#)
obscure :: (forall (rep1 :: RuntimeRep) (rep2 :: RuntimeRep)
(a :: TYPE rep1) (b :: TYPE rep2).
a -> b -> (# a, b #)) -> ()
obscure _ = ()
quux :: ()
quux = obscure (#,#)
-- It used to be that primops has no binding. However, as described in
-- Note [Primop wrappers] in PrimOp we now rewrite unsaturated primop
-- applications to their wrapper, which allows safe use of levity polymorphism.
primop :: forall (rep :: RuntimeRep) (a :: TYPE rep) b c.
a -> b -> (State# RealWorld -> (# State# RealWorld, c #))
-> State# RealWorld -> (# State# RealWorld, Weak# b #)
primop = mkWeak#
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