From b0a0c5556e668ee38462d71f41a20804bb5470fe Mon Sep 17 00:00:00 2001
From: Mike Sperber <sperber@deinprogramm.de>
Date: Fri, 5 Feb 2016 15:13:21 +0100
Subject: [PATCH] Docstrings and documentation for haskell-process-path-*.

(In the wake of #1112.)
---
 doc/haskell-mode.texi | 37 +++++++++++++++++++++++++++++++++++++
 haskell-customize.el  | 15 ++++++++++++---
 2 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/doc/haskell-mode.texi b/doc/haskell-mode.texi
index 22b8732b0..4f7293cc8 100644
--- a/doc/haskell-mode.texi
+++ b/doc/haskell-mode.texi
@@ -751,6 +751,43 @@ these keybindings:
 You have to load the module before it works, after that it will remember
 for the current GHCi session.
 
+@section Customizing
+
+@cindex customizing
+What kind of Haskell REPL @code{haskell-interactive-mode} will start up
+depends on the value of @code{haskell-process-type}.  This can be one of
+the symbols @code{auto}, @code{ghci}, @code{cabal-repl}, or
+@code{stack-ghci}.  If it's @code{auto}, the directory contents and
+available programs will be used to make a best guess at the
+process type.  The actual process type will then determine which
+variables @code{haskell-interactive-mode} will access to determine the
+program to start and its arguments:
+
+@itemize
+@item
+If it's @code{ghci}, @code{haskell-process-path-ghci} and
+@code{haskell-process-args-ghci} will be used.
+@item
+If it's @code{cabal-repl}, @code{haskell-process-path-ghci} and 
+@code{haskell-process-args-ghci}.
+@item
+If it's @code{stack-ghci}, @code{haskell-process-path-stack} and
+@code{haskell-process-args-stack-ghci} will be used.
+@end itemize
+
+With each of these pairs, the the @code{haskell-process-path-...}
+variable needs to be a string specifying the program path, or a list of
+strings where the first element is the program path and the rest are
+initial arguments.  The @code{haskell-process-args-...} is a list of
+strings specifying (further) command-line arguments.
+
+@vindex haskell-process-type
+@vindex haskell-process-path-ghci
+@vindex haskell-process-path-cabal
+@vindex haskell-process-path-stack
+@vindex haskell-process-args-ghci
+@vindex haskell-process-args-cabal-repl
+@vindex haskell-process-args-stack-ghci
 
 @node Editing Cabal files
 @chapter Editing Cabal files
diff --git a/haskell-customize.el b/haskell-customize.el
index b9c2efc70..0516acc5b 100644
--- a/haskell-customize.el
+++ b/haskell-customize.el
@@ -115,19 +115,28 @@ when showing type information about symbols."
 
 (defcustom haskell-process-path-ghci
   "ghci"
-  "The path for starting ghci."
+  "The path for starting ghci.
+This can either be a single string or a list of strings, where the
+first elements is a string and the remaining elements are arguments,
+which will be prepended to `haskell-process-args-ghci'."
   :group 'haskell-interactive
   :type '(choice string (repeat string)))
 
 (defcustom haskell-process-path-cabal
   "cabal"
-  "Path to the `cabal' executable."
+  "Path to the `cabal' executable.
+This can either be a single string or a list of strings, where the
+first elements is a string and the remaining elements are arguments,
+which will be prepended to `haskell-process-args-cabal-repl'."
   :group 'haskell-interactive
   :type '(choice string (repeat string)))
 
 (defcustom haskell-process-path-stack
   "stack"
-  "The path for starting stack."
+  "The path for starting stack.
+This can either be a single string or a list of strings, where the
+first elements is a string and the remaining elements are arguments,
+which will be prepended to `haskell-process-args-stack-ghci'."
   :group 'haskell-interactive
   :type '(choice string (repeat string)))