GHCi-7 not importing (some?) re-exported instances

[lpsmith]

Using import Module from the ghci prompt fails to bring some instances into scope. On the other hand, :m +Module does not appear to have this issue.

$ ghci
GHCi, version 7.0.1: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
ghci> import Data.Time
ghci> show `fmap` getCurrentTime

<interactive>:1:1:
    No instance for (Show UTCTime)
      arising from a use of `show'
    Possible fix: add an instance declaration for (Show UTCTime)
    In the first argument of `fmap', namely `show'
    In the expression: show `fmap` getCurrentTime
    In an equation for `it': it = show `fmap` getCurrentTime
(0.09 secs, 9682112 bytes)
ghci> :q
Leaving GHCi.


$ ghci
GHCi, version 7.0.1: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
ghci> :m +Data.Time
ghci> show `fmap` getCurrentTime
Loading package old-locale-1.0.0.2 ... linking ... done.
Loading package time-1.2.0.3 ... linking ... done.
"2011-04-01 17:41:21.108154 UTC"
ghci> 

Tested on 7.0.1, 7.0.2, and 7.0.3

[simonmar]

duplicate of #4832