Cabal-based syntax checker

[flycheck]

Cabal-based syntax checker

[gracjan]

Note:

Until this is done I'm using this diff:

-  :command ("ghc" "-Wall" "-fno-code"
+  :command ("ghc" "-Wall"
+            "-no-link" "-outputdir" "/tmp/flycheck-haskell" "-O0"

This has the following properties:

• caches results from checking to checking, greatly speeding up interaction
• enables template haskell

Of course /tmp/ should be changed to proper TMPDIR derived variable, but otherwise this change fixes problems with flycheck and bigger projects.

[latkins]

@gracjan I'm having the same issues with template haskell as you are, and have attempted to use the change you posted above. This has not worked for me - could you provide some more information about how you use it?

[gracjan]

I have done some more work in this department and have a rebased changes somewhere. I need to clean them up a little and resubmit. I hope to get there rather soon.

Meanwhile, can you copy&paste output of flycheck-compile? That would help to see if you are hitting same issue or something else.

[latkins]

@gracjan I managed to get your original diff to work now - I had forgotten to recompile to emacs bytecode. I would be interested in seeing your updated changes, though!

[swsnr]

Closing in favour of #45