Hello,
Apologies for this slightly off-topic question, but it may relate to
slime's `group' settings
(Much off this email is a copy of a post to gnu.emacs.help)
I am trying to display text following an underscore as a subscript and
following a caret as a superscript. By looking at various pieces of
code (tex-mode.el and pretty-greek.el from Pascal Bourgignon), I came
up with the following (which, of course does not work):
(defvar suscript-height-minimum 0)
(defvar suscript-height-ratio 0.8)
(defun suscript-height (height)
"Return the integer height of subscript/superscript font in 1/10
points.
Not smaller than the value set by `tex-suscript-height-minimum'."
(ceiling (max (if (integerp suscript-height-minimum)
suscript-height-minimum
;; For bootstrapping.
(condition-case nil
(* suscript-height-minimum
(face-attribute 'default :height))
(error 0)))
;; NB assumes height is integer.
(* height suscript-height-ratio))))
(defface superscript
'((t :height suscript-height))
"Face used for superscripts.")
(defface subscript
'((t :height suscript-height))
"Face used for subscripts.")
(defun suscript-match-regexp (escape-char)
"regexp for suscripted text match in common-lisp code"
(let ((terminating-string (format "_^ )$-")))
(format "%s\\(.*?\\)[%s]" escape-char
terminating-string terminating-string)))
(defvar subscript-match (suscript-match-regexp "_")
"Matches _whatever[_|^|SPACE|TAB|)")
(defvar superscript-match (suscript-match-regexp "\\^")
"Matches ^whatever[_|^|SPACE|TAB|)")
(defun pretty-suscript ()
"Load super&subscript keywords into `suscript-flk' and
load that into `font-lock-keywords'"
(interactive)
(setq suscript-flk
`((,subscript-match
(1 (face subscript display (raise 0.2))))
(,superscript-match
(1 (face superscript display (raise -0.2))))))
(font-lock-add-keywords nil suscript-flk))
(defun cancel-pretty-suscript ()
"Remove `suscript-flk' keywords from `font-lock-keywords'"
(interactive)
(font-lock-remove-keywords nil suscript-flk))
The contents `font-lock-keywords' are as follows:
(t
(("_\\(.*?\\)[_^ )$-]"
(1
(face subscript display
(raise 0.2))))
("\\^\\(.*?\\)[_^ )$-]"
(1
(face superscript display
(raise -0.2))))
...)
My question is whether I need to specify a group in the `defface'
commands. For example:
(defface superscript
'((t :height 0.8));;suscript-height))
"Face used for superscripts."
:group 'slime-mode-faces)
I found several groups in slime.el, and I am not sure which one to
apply in defface.
Thanks,
Mirko