Haskell Mode for Emacs                                        -*-text-*-
----------------------
Version number: $Name:  $.

This is the Haskell mode package for Emacs.  Its use should be mostly
self-explanatory if you're accustomed to Emacs.

When Emacs is started up, it normally runs a file called ~/.emacs located in
your home directory.  This file should contain all of your personal
customisations written as a series of Elisp commands.  In order to install
the Haskell mode, you have to tell Emacs where to find it.  This is done by
adding some commands to the init file.

Installation
------------

- If you are using XEmacs, the haskell-mode package may be available for
  installation through the XEmacs package UI.

- If you are using Debian, you may be able to install the package
  haskell-mode with a command like "apt-get install haskell-mode".

Otherwise:

- Download and unpack the basic mode and modules into a suitable directory,
  e.g. ~/lib/emacs/haskell-mode/ where ~ stands for your home directory.

- If you are using Emacs 21, you need an additional library, "syntax", from
  a later version of Emacs.  The one you can get as
  http://cvs.savannah.gnu.org/viewcvs/*checkout*/emacs/emacs/lisp/emacs-lisp/syntax.el?rev=1.16
  definitely works.

- Assuming you have placed the basic mode haskell-mode.el and the modules
  you want to use in the directory ~/lib/emacs/haskell-mode/, add the
  following command to your init file (~/.emacs):

    (load "~/lib/emacs/haskell-mode/haskell-site-file")

  This only loads the bare-bones haskell-mode. To make it useful, you
  need additional modules; you can use the haskell customize-group
  to edit the Haskell mode hook or, if you prefer manual setup, try
  adding the following lines according to which modules you want to use:

    (add-hook 'haskell-mode-hook 'turn-on-haskell-doc-mode)
    (add-hook 'haskell-mode-hook 'turn-on-haskell-indentation)
    ;;(add-hook 'haskell-mode-hook 'turn-on-haskell-indent)
    ;;(add-hook 'haskell-mode-hook 'turn-on-haskell-simple-indent)

  Note that the three indentation modules are mutually exclusive - add at
  most one.  Note that the line of code for simple indentation is commented
  out (using a preceeding ;) in preference for the more advanced
  indentation module.  Installation is now complete!

The other modules are automatically loaded when needed in the following way:

- Font locking: just turn it on via `global-font-lock-mode' or do
  (add-hook 'haskell-mode-hook 'font-lock-mode)

- Declaration scanning: just use M-x imenu or bind `imenu' to a key.  E.g.
  (global-set-key [(control meta down-mouse-3)] 'imenu) or you can also add
  it to the menubar with (add-hook 'haskell-mode-hook 'imenu-add-menubar-index)

- Interaction with inferior Haskell interpreter: just hit C-c C-z  or  C-c C-l.


Setup
-----

Normally, inf-haskell automatically finds ghci or hugs in your PATH, but if
that's not the case (common under Windows), or if you need to specify your
preference, just tell Emacs which executable to use with:

   (setq haskell-program-name "/some/where/ghci.exe")

If you want to use different settings when you use Cygwin Emacs and NTEmacs,
you can test the value of `system-type':

   (setq haskell-program-name
         (if (eq system-type 'cygwin)
             "/cygdrive/c/ghc/ghc-6.8.1/bin/ghcii.sh"
           "c:/ghc/ghc-6.8.1/bin/ghci.exe"))

Note that Cygwin binaries tend to interact poorly with NTEmacs, especially
w.r.t signal-handling.


Customization
-------------

Most customizations are on the functionality of a particular module.
See the documentation of that module for information on its
customisation.

There is also a wiki page listing tips and tricks at
http://trac.haskell.org/haskellmode-emacs/wiki/Tips

Known problems
--------------

It seems that some versions of XEmacs come without the fsf-compat package
(which provides functions such as `line-end-position') and it seems that
even if your XEmacs does have the fsf-compat package installed it does not
autoload its part.  Thus you may have to install the fsf-compat package and
add (require 'goto-addr) in your .emacs.


Multi-mode editing
------------------

For LaTeX-based literate Haskell, you might be interested in the
multiple major mode package haskell-latex.el (plus multi-mode.el) from
http://www.loveshack.ukfsn.org/emacs/.


Support
-------

Mailing list: http://projects.haskell.org/cgi-bin/mailman/listinfo/haskellmode-emacs
Bug tracker:  http://trac.haskell.org/haskellmode-emacs/