Allow aliases in GHCi module imports

[tibbe]

It would be convenient if it was possible to import a package in GHCi under another name.

:m +Data.ByteString.Lazy.Char8 as B

This is especially useful with modules like Data.ByteString which names collide with Prelude.

[igloo]

This would also keep the prompt width down, which would be nice.

[guest]

Speaking for myself, I really hope that when this is fixed, it'll be easy to load modules qualified via the GHC API. This would let me fix mueval so things like 'mueval -e "Map.map (+1) $ Map.fromList [(1,2)]' could work.

(Which is valuable since I use mueval in Lambdabot, and Lambdabot users expect to be able to use qualified imports.)

[igloo]

Many CCed, so making high priority

[simonmar]

This would be subsumed by

#2362

allow full import syntax in GHCi

.

[simonmar]

closing to merge with #2362