#+TITLE: emacs notes
#+SHORT-TITLE: emacs
#+KEYWORDS: lisp, emacs
#+DESCRIPTION: emacs notes

#+BEGIN(menu):left
[[toc][]]
#+END

* emacs
For people familiar with lisp emacs has no competitors; but even before learning lisp it was a handy tool for me and
I used it for c.a. 10 years. Here I collect my emacs tips/notes and pieces of code.

* Bugs
Somehow emacs does not handle remote connections well: it may freeze up and become immortal (immune even to [[src:kill -9]]).
So instead of [[src:C-x C-f /ssh:server.com:/path/to/file.txt]] I prefer mounting remote directory into [[src:/mnt/]]
and then access it with emacs as a local file.

* TeX-lisp manual
I do not remember all Lisp functions, so it is helpful to quickly access extended articles from the TeX-lisp manual
when updating a [[src:.lisp]] file.

[[https://github.com/ruricolist/dpans2texi][dpans2texi]] is a useful software which transforms TeX manuals into [[https://www.gnu.org/software/texinfo/][texinfo format]].
The latter is understood by emacs, so, for example, when you write lisp code,
you can get documentation (better than what slime provides) for lisp functions and symbols by pressing [[src:C-c C-d h]].

Unfortunately it did not work for me out of the box, so I had to patch it.

My [[files/dpans2texi.patch][patch]]
1. fixes [[src:dpi.texi]] encoding,
2. does a couple of fixes in [[src:dp.texi]],
3. adds treatment of TeX macro [[src:it]] to [[src:dpans2texi.el]],
4. removes non-working redefinition of [[src:@code]] from [[src:dpi.texi]].

This patch is a quick fix; it can be improved (sometimes I note strange symbols in the emacs info-buffer).
Unfortunately, many packages available from quicklisp are not covered in the standard TeX-lisp manual;
If/when I have time, I will slowly update the standard TeX-lisp manual with info on (my favorite) common-lisp packages.

* Patching dpans2texi
The original dpans2texi project was erased on github, so now one can use [[https://github.com/ruricolist/dpans2texi][its clone]].

Install original [[https://github.com/ruricolist/dpans2texi][dpans2texi]] and patch it:

#+BEGIN(src):shell
git clone https://github.com/ruricolist/dpans2texi
cd dpans2texi
wget chalaev.com/files/dpans2texi.patch
patch -p1 < dpans2texi.patch
make clean; rm *.tex
./configure --prefix=$HOME/local
make wget && make && make install
#+END

(See also [[https://github.com/ruricolist/dpans2texi][dpans2texi]]  manual).

* Configuring emacs
After the following piece of code is evaluated, we can get help on lisp symbols using standard slime key combination (default [[src:C-c C-d h]]). 
In order to activate info-files produced by [[https://github.com/ruricolist/dpans2texi][dpans2texi]] insert the following into your [[src:\~\/.emacs]] file:
#+BEGIN(src):elisp
(require 'info-look)
(setq Info-additional-directory-list 
  (list(substitute-in-file-name "$HOME/local/share/info")))

(with-eval-after-load "slime"
  (info-lookup-add-help
   :mode 'lisp-mode
   :regexp "[^][()'\" \t\n]+"
   :ignore-case t
   :doc-spec '(("(ansicl)Symbol Index" nil nil nil)))
    
  (info-lookup-add-help
   :mode 'slime-repl-mode
   :regexp "[^][()'\" \t\n]+"
   :ignore-case t
   :doc-spec '(("(ansicl)Symbol Index" nil nil nil)))

  (defvar slime-old-documentation-lookup-function
    (if (boundp 'slime-documentation-lookup-function)
	slime-documentation-lookup-function))
  
  (defun slime-ansicl-lookup (symbol-name)
    (interactive (list (slime-read-symbol-name "Symbol: ")))
    (info-lookup-symbol symbol-name 'lisp-mode))
  
  (setq slime-documentation-lookup-function 'slime-ansicl-lookup)
  (setq slime-ansicl-lookup (symbol-function 'slime-ansicl-lookup)))
#+END