Inconsistent import of instances in GHCi

Issuing import M in GHCi does not bring the same instances into scope as issuing :m + M and loading a file that contains import M do.

For example, the module Control.Applicative imports Control.Monad.Instances which defines a Functor instance for ((->) r). The following GHCi session demonstrates that this instance is not in scope after issuing an import command in GHCi but it is in scope after issuing an :m + command. It is also in scope after loading a file that imports Control.Applicative.

Prelude> fmap id id ()

<interactive>:1:1:
    No instance for (Functor ((->) ()))
      arising from a use of `fmap'
    Possible fix: add an instance declaration for (Functor ((->) ()))
    In the expression: fmap id id ()
    In an equation for `it': it = fmap id id ()
Prelude> import Control.Applicative
Prelude Control.Applicative> fmap id id ()

<interactive>:1:1:
    No instance for (Functor ((->) ()))
      arising from a use of `fmap'
    Possible fix: add an instance declaration for (Functor ((->) ()))
    In the expression: fmap id id ()
    In an equation for `it': it = fmap id id ()
Prelude Control.Applicative> :m + Control.Applicative
Prelude Control.Applicative> fmap id id ()
()

I expected that issuing an import command in GHCi has the same effect as issuing an :m + command or loading a file with an import statement.

Trac metadata

Trac field	Value
Version	7.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	GHCi
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture