Strange behavior of GHC by writing the types in GHCi

• A: you type :set +t then you write 1:2, the answer is:\\

Prelude> :set +t

Prelude> 1:2

<interactive>:8:1: error:
    * Non type-variable argument in the constraint: Num [a]
      (Use FlexibleContexts to permit this)
    * When checking the inferred type
        it :: forall a. (Num [a], Num a) => [a]

\\

• B: you type :t 1:2, the answer is:\\

Prelude> :t 1:2
1:2 :: (Num [a], Num a) => [a]

\\ There is an obvious bug. Don't answer me that this behavior is correct, please! The two answers should be the same. Either answer A or answer B.

Trac metadata

Trac field	Value
Version	8.0.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	GHCi
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