diff options
Diffstat (limited to 'lisp/progmodes/prog-mode.el')
| -rw-r--r-- | lisp/progmodes/prog-mode.el | 106 |
1 files changed, 68 insertions, 38 deletions
diff --git a/lisp/progmodes/prog-mode.el b/lisp/progmodes/prog-mode.el index e2700414636..b3ed328bd72 100644 --- a/lisp/progmodes/prog-mode.el +++ b/lisp/progmodes/prog-mode.el @@ -54,63 +54,93 @@ instead." (end (progn (forward-sexp 1) (point)))) (indent-region start end nil)))) -(defvar prog-prettify-symbols-alist nil) - -(defcustom prog-prettify-symbols nil - "Whether symbols should be prettified. -When set to an alist in the form `((STRING . CHARACTER)...)' it -will augment the mode's native prettify alist." - :type '(choice - (const :tag "No thanks" nil) - (const :tag "Mode defaults" t) - (alist :tag "Mode defaults augmented with your own list" - :key-type string :value-type character)) - :version "24.4") - -(defun prog--prettify-font-lock-compose-symbol (alist) - "Compose a sequence of ascii chars into a symbol. +(defvar-local prettify-symbols-alist nil + "Alist of symbol prettifications. +Each element looks like (SYMBOL . CHARACTER), where the symbol +matching SYMBOL (a string, not a regexp) will be shown as +CHARACTER instead.") + +(defun prettify-symbols--compose-symbol (alist) + "Compose a sequence of characters into a symbol. Regexp match data 0 points to the chars." ;; Check that the chars should really be composed into a symbol. (let* ((start (match-beginning 0)) (end (match-end 0)) (syntaxes (if (eq (char-syntax (char-after start)) ?w) - '(?w) '(?. ?\\)))) - (if (or (memq (char-syntax (or (char-before start) ?\ )) syntaxes) - (memq (char-syntax (or (char-after end) ?\ )) syntaxes) - (nth 8 (syntax-ppss))) + '(?w) '(?. ?\\))) + match) + (if (or (memq (char-syntax (or (char-before start) ?\s)) syntaxes) + (memq (char-syntax (or (char-after end) ?\s)) syntaxes) + ;; syntax-ppss could modify the match data (bug#14595) + (progn (setq match (match-string 0)) (nth 8 (syntax-ppss)))) ;; No composition for you. Let's actually remove any composition ;; we may have added earlier and which is now incorrect. (remove-text-properties start end '(composition)) ;; That's a symbol alright, so add the composition. - (compose-region start end (cdr (assoc (match-string 0) alist))))) + (compose-region start end (cdr (assoc match alist))))) ;; Return nil because we're not adding any face property. nil) -(defun prog-prettify-font-lock-symbols-keywords () - (when prog-prettify-symbols - (let ((alist (append prog-prettify-symbols-alist - (if (listp prog-prettify-symbols) - prog-prettify-symbols - nil)))) - `((,(regexp-opt (mapcar 'car alist) t) - (0 (prog--prettify-font-lock-compose-symbol ',alist))))))) +(defun prettify-symbols--make-keywords () + (if prettify-symbols-alist + `((,(regexp-opt (mapcar 'car prettify-symbols-alist) t) + (0 (prettify-symbols--compose-symbol ',prettify-symbols-alist)))) + nil)) -(defun prog-prettify-install (alist) -"Install prog-mode support to prettify symbols according to ALIST. +(defvar-local prettify-symbols--keywords nil) -ALIST is in the format `((STRING . CHARACTER)...)' like -`prog-prettify-symbols'. +;;;###autoload +(define-minor-mode prettify-symbols-mode + "Toggle Prettify Symbols mode. +With a prefix argument ARG, enable Prettify Symbols mode if ARG is +positive, and disable it otherwise. If called from Lisp, enable +the mode if ARG is omitted or nil. + +When Prettify Symbols mode and font-locking are enabled, symbols are +prettified (displayed as composed characters) according to the rules +in `prettify-symbols-alist' (which see), which are locally defined +by major modes supporting prettifying. To add further customizations +for a given major mode, you can modify `prettify-symbols-alist' thus: + + (add-hook 'emacs-lisp-mode-hook + (lambda () + (push '(\"<=\" . ?≤) prettify-symbols-alist))) + +You can enable this mode locally in desired buffers, or use +`global-prettify-symbols-mode' to enable it for all modes that +support it." + :init-value nil + (if prettify-symbols-mode + ;; Turn on + (when (setq prettify-symbols--keywords (prettify-symbols--make-keywords)) + (font-lock-add-keywords nil prettify-symbols--keywords) + (setq-local font-lock-extra-managed-props + (cons 'composition font-lock-extra-managed-props)) + (font-lock-fontify-buffer)) + ;; Turn off + (when prettify-symbols--keywords + (font-lock-remove-keywords nil prettify-symbols--keywords) + (setq prettify-symbols--keywords nil)) + (when (memq 'composition font-lock-extra-managed-props) + (setq font-lock-extra-managed-props (delq 'composition + font-lock-extra-managed-props)) + (with-silent-modifications + (remove-text-properties (point-min) (point-max) '(composition nil)))))) + +(defun turn-on-prettify-symbols-mode () + (when (and (not prettify-symbols-mode) + (local-variable-p 'prettify-symbols-alist)) + (prettify-symbols-mode 1))) -Internally, `font-lock-add-keywords' is called." - (setq-local prog-prettify-symbols-alist alist) - (let ((keywords (prog-prettify-font-lock-symbols-keywords))) - (if keywords (font-lock-add-keywords nil keywords)))) +;;;###autoload +(define-globalized-minor-mode global-prettify-symbols-mode + prettify-symbols-mode turn-on-prettify-symbols-mode) ;;;###autoload (define-derived-mode prog-mode fundamental-mode "Prog" "Major mode for editing programming language source code." - (set (make-local-variable 'require-final-newline) mode-require-final-newline) - (set (make-local-variable 'parse-sexp-ignore-comments) t) + (setq-local require-final-newline mode-require-final-newline) + (setq-local parse-sexp-ignore-comments t) ;; Any programming language is always written left to right. (setq bidi-paragraph-direction 'left-to-right)) |