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ado005.hs:8:3: error:
• Could not deduce (Monad f) arising from a do statement
from the context: Applicative f
bound by the type signature for:
test :: forall (f :: * -> *).
Applicative f =>
(Int -> f Int) -> f Int
at ado005.hs:6:1-48
Possible fix:
add (Monad f) to the context of
the type signature for:
test :: forall (f :: * -> *).
Applicative f =>
(Int -> f Int) -> f Int
• In a stmt of a 'do' block: x <- f 3
In the expression:
do x <- f 3
y <- f x
return (x + y)
In an equation for ‘test’:
test f
= do x <- f 3
y <- f x
return (x + y)
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