Re: Minor mode for colouring plain tex lowercase greek letters

[michael-franzese]

Have put the following code te highlight greek letters using a minor mode
for texinfo-mode and the plani tex colouring commands \alpha \beta \gamma
are not being coloured.


(defun insert-ptex ()
  (interactive)
  (insert "ptex"))

(defvar ptex-mode-map
  (let ((map (make-keymap)))
    (define-key map (kbd "C-c t") 'insert-ptex)
    map)
  "Key map for use when variable `ptex-mode' is non-nil.")

(defvar ptex-mode-hook nil
  "Hook called when variable `ptex-mode' is non-nil.")

(define-minor-mode ptex-mode
  "Minor mode for colouring plain tex keywords."
  :init-value nil
  :global nil
  :lighter " ptex"
  :keymap ptex-mode-map
  (run-hooks 'ptex-mode-hook))

(add-hook 'texinfo-mode-hook 'ptex-mode)

(defface colour-greek-category
  '((default :inherit bold)
    (((class color) (min-colors 88) (background light))
     :foreground "#00FFFF")
    (((class color) (min-colors 88) (background dark))
     :foreground "#00FFFF")
    (t :inherit font-lock-builtin-face))
  "Face for header category entry.")

(defconst ptex-greek-keywords
  '(("\\\\\\<\\(alpha\\|beta\\|gamma\\)\\>"
     (1 'colour-greek-category)))
  "Rules to apply font-lock highlighting.")

(defun ptex-assign-font-greek-keywords ()
  "Font-lock setup for `ptex-greek-keywords'."
  (font-lock-flush (point-min) (point-max))
  (if ptex-mode
      (font-lock-add-keywords nil ptex-greek-keywords t)
    (font-lock-remove-keywords nil ptex-greek-keywords))
  (font-lock-flush (point-min) (point-max)))

 (add-hook 'texinfo-mode-hook #'ptex-assign-font-greek-keywords)

(provide 'ptex-mode)





> Sent: Monday, January 11, 2021 at 9:10 PM
> From: michael-franzese@gmx.com
> To: "Help Gnu Emacs" <help-gnu-emacs@gnu.org>
> Subject: Minor mode for colouring plain tex lowercase greek letters
>
> Am trying to write a minor made to highlight tex keywords.  I am starting
> with the lowercase greek letters: \alpha, \beta, \gamma, \delta, \epsilon,
> \zeta, \eta, \theta, \iota, \kappa, \lambda, \mu, \nu, \xi.
>
> Do not know how I can set the lowercase greek letters to some colour.
>
> I would have to assign a face to each regexp group rather than defining my 
> own faces.
> Reuse the font-lock faces that one can find on M-x find-library RET faces RET.
>
>
>