Puzzling (to me) type error message

[Max Bolingbroke]

2009/3/24 Colin Adams <colinpauladams at googlemail.com>:
> UI.hs:625:45: Not in scope: type constructor or class `Move.Move'
>
> If I then comment-out the type signature for run_ai, it compiles fine
> with the following warning message:
>
> UI.hs:626:0:
>    Warning: Definition but no type signature for `run_ai'
>             Inferred type: run_ai :: Chan Non_interactive_state
>                                      -> Chan Move.Move
>                                      -> IO ()

Have you actually imported the Move.Move type? GHC /can/ suggest a
type signature that includes type constructors that you haven't
imported, but which show up in e.g. the types of imported functions.

Cheers,
Max