Why suddenly can't find module?

I have two files in the same folder, Eval.hs and Data.hs, module in开发者_开发百科 Eval.hs imports module TI.Data in Data.hs, when I try to load Eval.hs in the interactive (in emacs haskell mode: Ctrl-c, Ctrl l), it said it can't find the module defined in Data.hs, but it loaded successfully before, why suddenly it can't?? btw, I noticed that the first time I execute Ctrl-c, Ctrl l, the interative window:

GHCi, version 6.12.1: http://www.haskell.org/ghc/  :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Prelude> :cd ~/.cabal/                                                          
Prelude> :load "../hs/TI/Eval.hs"                                               

../hs/TI/Eval.hs:2:7:                                                           
    Could not find module `TI.Data':
      Use -v to see a list of the files searched for.
Failed, modules loaded: none.

I sometimes have this same problem with haskell-mode on Emacs. My workaround is to

Prelude> :cd ~/hs/TI
Prelude> :load "Eval.hs"

Now when you want to reload the module you have to use

Prelude> :r 

instead of Ctrl-C, Ctrl-l.

If someone knows a better way, please let me know.

-deech

Try:

Prelude> :cd ~/hs
Prelude> :load "TI/Eval.hs"

If the modules are actually like Subdirectory.Contains.A then the working directory needs to be the directory Subdirectory.

try adding

(inferior-haskell-find-project-root nil)

to your custom set variables. It will no longer :cd.

a much better solution would be finding out why the function in inf-haskell.el doesn't quite work

Simply run

:set -isrc -imyothersrcdir

To add any source directories. You can put this line in a .ghci file in the directory from which you run GHCi.

Alternatively just use cabal repl which does this for you based on your cabal file.