Auctex: how to cause math mode dollars to be closed automatically with electric-pair

Question

I use electric-pair mode to cause brackets to be automatically closed for me, so that when I enter (, { or [, the closing bracket is automatically also entered into the buffer and the cursor is placed between them. However, I cannot seem to get it to treat $ the same way. Perhaps it is related to the fact that TeX-insert-dollar is bound to $, and that presumably electric-pair doesn't treat $ the same way as (. I've tried fiddling along these lines, but I can't get the behaviour I want.

Answer 1

In the end it was simpler than I thought.

(electric-pair-mode)
(add-hook 'LaTeX-mode-hook
          '(lambda ()
            (define-key LaTeX-mode-map (kbd "$") 'self-insert-command)))

This just removes the TeX-insert-dollar binding to $ and somehow (electric-pair-mode) takes over and realises that $ is a bracket in this context.

Answer 2

For inserting stuff in LaTeX mode I use the following code in my .emacs:

(defun brf-TeX-Inserting (sta stb stc num)
  " after entering stb insert stc and go back with the cursor by num positions.
    With prefix nothings gets replaced. If the previous char was sta nothing will be 
    replaces as well." 
  (if (null current-prefix-arg)
      (progn
        (if (= (preceding-char) sta )
            (insert stb)
          (progn (insert stc) (backward-char num))))
    (insert stb)))

(defun brf-TeX-dollarm () (interactive) (brf-TeX-Inserting ?\\ "$"  "$$" 1))

(add-hook 'LaTeX-mode-hook
   (function (lambda ()
       (local-set-key (kbd "$")      'brf-TeX-dollarm))))

Then typing $ inserts the pair of $$ and puts the cursor in between.

Answer 3

I use cdlatex-mode for this (EmacsWiki, elisp). It has many other features to make typing easier (such as automatic insertion of paired \begin{environment} and \end{environment} for any environment, of paired \left and \right, typing `a to get \alpha etc., and insertion of paired {} (with the cursor placed inside) every time you type _ or ^). It takes a while getting used to its usefulness, but it's very convenient once you get familiar.