I setted `haskell-process-type` to 'ghci.
I evaluated a simple haskell src block, but it reports I need have a
`*haskell*` inferior. Then I executed command [M-x run-haskell].
Then I get error:

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
  expand-file-name(nil)
  locate-dominating-file(nil "cabal.sandbox.config")
  haskell-process-type()
  haskell-program-name-with-args()
  inferior-haskell-start-process()
  inferior-haskell-process()
  run-haskell()
  funcall-interactively(run-haskell)
  call-interactively(run-haskell record nil)
  command-execute(run-haskell record)
  #f(compiled-function (cmd) #<bytecode 0x244f2f9>)("run-haskell")
  ivy-call()
  ivy-read("M-x " [special-lispy-clone
  ....
  counsel-M-x()
  funcall-interactively(counsel-M-x)
  call-interactively(counsel-M-x nil nil)
  command-execute(counsel-M-x)

[stardiviner]           <Hack this world!>      GPG key ID: 47C32433
IRC(freeenode): stardiviner                     Twitter:  @numbchild
Key fingerprint = 9BAA 92BC CDDD B9EF 3B36  CB99 B8C4 B8E5 47C3 2433
Blog: http://stardiviner.github.io/

On Wed, Nov 15, 2017 at 11:35 PM, Nick Dokos <ndokos@gmail.com> wrote:

> "numbchild@gmail.com" <numbchild@gmail.com> writes:
>
> > I checked out your answer, I have meet all your said requirements. GHCi,
> inf-haskell (after I installed package haskell-mode) and setting
> `haskell-program-name`, I found there is no
> > `defcustom` variable option named `haskell-program-name` at all.
>
> You probably need to set haskell-process-type to ghci. If that works,
> please let me know and I'll update the answer on SO.
>
> >
> > [stardiviner]           <Hack this world!>      GPG key ID: 47C32433
> > IRC(freeenode): stardiviner                     Twitter:  @numbchild
> > Key fingerprint = 9BAA 92BC CDDD B9EF 3B36  CB99 B8C4 B8E5 47C3 2433
> > Blog: http://stardiviner.github.io/
> >
> > On Wed, Nov 15, 2017 at 9:17 PM, numbchild@gmail.com <
> numbchild@gmail.com> wrote:
> >
> >     I required `(require 'inf-haskell)` But have not found the command
> `inf-haskell` to start inferior process.
> >
> >     [stardiviner]           <Hack this world!>      GPG key ID: 47C32433
> >     IRC(freeenode): stardiviner                     Twitter:  @numbchild
> >     Key fingerprint = 9BAA 92BC CDDD B9EF 3B36  CB99 B8C4 B8E5 47C3 2433
> >     Blog: http://stardiviner.github.io/
> >
> >     On Mon, Nov 13, 2017 at 11:43 PM, Nick Dokos <ndokos@gmail.com>
> wrote:
> >
> >         stardiviner <numbchild@gmail.com> writes:
> >
> >         > When I execute the following Haskell src block:
> >         >
> >         > ```
> >         >
> >         > #+BEGIN_SRC haskell :session :tangle "Data/Code/hello_world.hs"
> >         > main :: IO ()
> >         > main = do
> >         >   putStrLn "Hello, World!"
> >         > #+END_SRC
> >         >
> >         > ```
> >         >
> >         > It reports error:
> >         >
> >         > ```
> >         >
> >         > Debugger entered--Lisp error: (file-missing "Cannot open load
> file" "No
> >         > such file or directory" "inf-haskell")
> >         >   require(inf-haskell)
> >
> >         See my answer to this SO question:
> >
> >           https://stackoverflow.com/questions/42081379/how-to-set-
> up-org-babel-for-haskell-with-stack
> >
> >         for some details on setting up the environment.
> >
> >         --
> >         Nick
> >
>
> --
> Nick
>
>
>