Pretty org-entities in org-mode buffers

["Eric Schulte" <schulte.eric@gmail.com>]

Hi,

Recently I've been making use of org-entites for exporting my greek/math
heavy class notes to HTML.  I'm really loving the results.

This morning I've started playing around with the below function
`org-pretty-entities', which is adapted from Phil Hagelberg's
`pretty-lambdas'[1].  Calling this function in an org-mode buffer will
have the effect of fontifying all org-entities text strings as the
character which they represent, so \Delta is replaced with Δ, \lambda
with λ, \in with ∈, and so forth.

I've just started playing with this, and I make no guarantees as to it's
safety or utility, but I was very pleasantly surprised by the simplicity
of the function, and how nice it's been to see my special characters
appear in org-mode buffers as I type.

#+begin_src emacs-lisp :results silent
  (defun org-pretty-entities ()
    (interactive)
    (font-lock-add-keywords
     nil (mapcar
          (lambda (el)
            (list
             (concat "(?\\(" (regexp-quote "\\") (nth 0 el) "[\s]" "\\)")
             `(0 (progn (compose-region (match-beginning 1) (- (match-end 1) 1)
                                        ,(nth 6 el)) nil))))
          org-entities)))
  
  (org-pretty-entities)
#+end_src

To try this out, just evaluate the above code block inside of an
org-mode buffer, then starting typing out org-entities.

Hope others find this useful.

Best -- Eric

Footnotes: 
[1]  http://github.com/technomancy/emacs-starter-kit/blob/master/starter-kit-defuns.el#L135