Interactive mode cannot work for stack ghci

[zhouqiji]

HI, appreciate you guys notice this issue,
My working environment is: WIndows 10 64 bit, emacs 24.5.1

My problem is that when I start interactive mode in eamcs, it would say:

 "The Haskell process `haskell` has died."

And the process log shows:

("Starting inferior stack GHCi process using stack" "haskell" nil "stack" "ghci" "--ghc-options=-ferror-spans")

-> Prelude.putStrLn ""
:set -v1
:set +c
-> :set prompt "\4"
-> :set prompt2 "λ| "
<- Run from outside a project, using implicit global project config
<- Error parsing targets: The specified targets matched no packages.
   Perhaps you need to run 'stack init'?
   Warning: build failed, but optimistically launching GHCi anyway
<- Configuring GHCi with the following packages: 
   GHCi, version 7.10.3: http://www.haskell.org/ghc/  :? for help
<- Ok, modules loaded: none.
   Prelude> 
   Prelude> Prelude> unknown option: 'c'
   Prelude> �Leaving GHCi.
Event: "finished"
Process reset.

May I ask how to solve it? Thanks!

[geraldus]

Looks like something wrong with working directory on Windows.

[geraldus]

Hmm… I overviewed haskell-interactive.el and did not found a piece of code where project's root folder lookup occur.

[zhouqiji]

Thanks for your reply，
It works well on my ubuntu machine.
But still cannot work for windows......
Is it possible the stack problem?

[geraldus]

@zhouqiji I can't be certain, sorry for delay
@gracjan can tell how interactive mode determines the project directory (I see no clue in sources)?

[gracjan]

It tries to find *.cabal by going up the directories.

[geraldus]

Do you know how it gets current directory (from where to start)?

[gracjan]

@geraldus: I do not think that current working directory is managed somehow differently under unix versus windows.

I'm working on a testing environment for Windows so if somebody wants to write a test case for this particular issue and make sure it works on Unix then we will be able to also check same scenario on Windows.

[fice-t]

@zhouqiji I tried this out on a Windows 7 box and I got it fixed by:

1. Following step 3 in https://www.haskell.org/platform/windows.html#windows
2. Running stack setup.

Does that work for you?

[zhouqiji]

@fice-t Appreciate your help, I will try it. :)

[bugczw]

I have the same problem,but I don't know how to solve. The haskell process log is

`("Starting inferior stack GHCi process using stack" "haskell" nil "stack" "ghci" "--ghc-options=-ferror-spans")
-> Prelude.putStrLn ""
:set -v1
:set +c
-> :set prompt "\4"
-> :set prompt2 "λ| "
<-
Note: No local targets specified, so a plain ghci will be started with no package hiding or package
options.

     If you want to use package hiding and options, then you can try one of the following:
     
     * If you want to start a different project configuration
       than C:\sr\global-project\stack.yaml, then you can use stack init to create a new stack.yaml
       for the packages in the current directory. 
       
     * If you want to use the project configuration
       at C:\sr\global-project\stack.yaml, then you can add to its 'packages' field.

<- Configuring GHCi with the following packages:

<- GHCi, version 8.6.3: http://www.haskell.org/ghc/ :? for help

<- Loaded GHCi configuration from C:\Users\bugczw\AppData\Local\Temp\haskell-stack-ghci\2a3bbd58\ghci-script
Prelude>
Prelude> Prelude> Prelude> �Leaving GHCi.`