Confirmed with minimal Emacs config.
I'm using latest Emacs which build from source code, and latest version
Org-mode which load from source code.

Here is the steps to reproduce the issue:
1. emacs-minimal-init (command which load minimal init file)
2. [M-x run-haskell] ; load haskell inferior for `ob-haskell`.
3. press [C-c C-c] on haskell src block like this:

#+BEGIN_SRC haskell :session "*haskell*"
1 + 9
#+END_SRC

I got error:

#+BEGIN_EXAMPLE
Debugger entered--Lisp error: (error "‘org-babel-script-escape’ expects a
string")
  signal(error ("‘org-babel-script-escape’ expects a string"))
  error("`org-babel-script-escape' expects a string")
  org-babel-script-escape(nil)
  org-babel-execute:haskell("2 + 8" ((:colname-names) (:rowname-names)
(:result-params "replace") (:result-type . value) (:results . "replace")
(:exports . "code") (:session . "none") (:cache . "no") (:noweb . "no")
(:hlines . "no") (:tangle . "no") (:padlines . "no")))
  org-babel-execute-src-block(nil ("haskell" "2 + 8" ((:colname-names)
(:rowname-names) (:result-params "replace") (:result-type . value)
(:results . "replace") (:exports . "code") (:padlines . "no") (:tangle .
"no") (:hlines . "no") (:noweb . "no") (:cache . "no") (:session . "none"))
"" nil 110 "(ref:%s)"))
  org-ctrl-c-ctrl-c(nil)
  funcall-interactively(org-ctrl-c-ctrl-c nil)
  call-interactively(org-ctrl-c-ctrl-c nil nil)
  command-execute(org-ctrl-c-ctrl-c)
#+END_EXAMPLE

In ~*haskell*~ buffer:

#+BEGIN_EXAMPLE
GHCi, version 8.0.1: http://www.haskell.org/ghc/  :? for help
Loaded GHCi configuration from /home/stardiviner/.ghci
λ> 2 + 8
"org-babel-haskell-eoe"
10
λ> "org-babel-haskell-eoe"
λ> 2 + 8
"org-babel-haskell-eoe"
10
λ> "org-babel-haskell-eoe"
λ>
#+END_EXAMPLE

In other way: when I start haskell inferior process with command:
[M-x haskell-interactive-bring].

The error is:

#+BEGIN_EXAMPLE
Debugger entered--Lisp error: (error "Buffer *haskell* does not exist or
has no process")
  signal(error ("Buffer *haskell* does not exist or has no process"))
  error("Buffer %s does not exist or has no process" #<buffer *haskell*>)
  org-babel-execute:haskell("main :: IO ()\nmain = do\n  putStrLn \"Hello,
World!\"" ((:colname-names) (:rowname-names) (:result-params "replace")
(:result-type . value) (:results . "replace") (:exports . "code") (:session
. "none") (:cache . "no") (:noweb . "no") (:hlines . "no") (:tangle . "no")
(:padlines . "no")))
  org-babel-execute-src-block(nil ("haskell" "main :: IO ()\nmain = do\n
 putStrLn \"Hello, World!\"" ((:colname-names) (:rowname-names)
(:result-params "replace") (:result-type . value) (:results . "replace")
(:exports . "code") (:padlines . "no") (:tangle . "no") (:hlines . "no")
(:noweb . "no") (:cache . "no") (:session . "none")) "" nil 53 "(ref:%s)"))
  org-ctrl-c-ctrl-c(nil)
  funcall-interactively(org-ctrl-c-ctrl-c nil)
  call-interactively(org-ctrl-c-ctrl-c nil nil)
  command-execute(org-ctrl-c-ctrl-c)
#+END_EXAMPLE

 *Problem*:

 =haskell-interactive-bring= started =*haskell*= process buffer does not
work with
 Org-mode Babel ob-haskell's session =*haskell*=.


But I have process buffer ~*haskell*~ running.

This is weird.

I used to report error at here:
https://github.com/haskell/haskell-mode/issues/1429



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