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T14884.hs:4:5: error: [GHC-88464]
• Found hole: _ :: (a0 -> IO ()) -> String -> IO ()
Where: ‘a0’ is an ambiguous type variable
• In the expression: _ print "abc"
In an equation for ‘x’: x = _ print "abc"
• Relevant bindings include x :: IO () (bound at T14884.hs:4:1)
Valid hole fits include
mapM_ :: forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
(a -> m b) -> t a -> m ()
with mapM_ @[] @IO @Char @()
(imported from ‘Prelude’ at T14884.hs:1:8-13
(and originally defined in ‘Data.Foldable’))
foldMap :: forall (t :: * -> *) m a.
(Foldable t, Monoid m) =>
(a -> m) -> t a -> m
with foldMap @[] @(IO ()) @Char
(imported from ‘Prelude’ at T14884.hs:1:8-13
(and originally defined in ‘Data.Foldable’))
($) :: forall a b. (a -> b) -> a -> b
with ($) @GHC.Types.LiftedRep @String @(IO ())
(imported from ‘Prelude’ at T14884.hs:1:8-13
(and originally defined in ‘GHC.Base’))
($!) :: forall a b. (a -> b) -> a -> b
with ($!) @GHC.Types.LiftedRep @String @(IO ())
(imported from ‘Prelude’ at T14884.hs:1:8-13
(and originally defined in ‘GHC.Base’))
id :: forall a. a -> a
with id @(String -> IO ())
(imported from ‘Prelude’ at T14884.hs:1:8-13
(and originally defined in ‘GHC.Base’))
T14884.hs:4:7: error: [GHC-39999]
• Ambiguous type variable ‘a0’ arising from a use of ‘print’
prevents the constraint ‘(Show a0)’ from being solved.
Probable fix: use a type annotation to specify what ‘a0’ should be.
Potentially matching instances:
instance (Show a, Show b) => Show (Either a b)
-- Defined in ‘Data.Either’
instance Show Ordering -- Defined in ‘GHC.Show’
...plus 26 others
...plus 28 instances involving out-of-scope types
(use -fprint-potential-instances to see them all)
• In the first argument of ‘_’, namely ‘print’
In the expression: _ print "abc"
In an equation for ‘x’: x = _ print "abc"
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