diff options
| -rw-r--r-- | emacs/Makefile.am | 2 | ||||
| -rw-r--r-- | emacs/skribilo.el | 114 |
2 files changed, 115 insertions, 1 deletions
diff --git a/emacs/Makefile.am b/emacs/Makefile.am index 8afd259..85d0027 100644 --- a/emacs/Makefile.am +++ b/emacs/Makefile.am @@ -1,5 +1,5 @@ EXTRA_DIST = skribe.el.in -lisp_DATA = skribe.el +lisp_DATA = skribe.el skribilo.el CLEANFILES = $(lisp_DATA) diff --git a/emacs/skribilo.el b/emacs/skribilo.el new file mode 100644 index 0000000..9f9bc52 --- /dev/null +++ b/emacs/skribilo.el @@ -0,0 +1,114 @@ +;;; skribilo.scm -- The Skribilo document processor. +;;; +;;; Copyright © 2021 Arun Isaac <arunisaac@systemreboot.net> +;;; +;;; This file is part of Skribilo. +;;; +;;; Skribilo is free software: you can redistribute it and/or modify +;;; it under the terms of the GNU General Public License as published by +;;; the Free Software Foundation, either version 3 of the License, or +;;; (at your option) any later version. +;;; +;;; Skribilo is distributed in the hope that it will be useful, +;;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +;;; GNU General Public License for more details. +;;; +;;; You should have received a copy of the GNU General Public License +;;; along with Skribilo. If not, see <http://www.gnu.org/licenses/>. + +(require 'scheme) + +(defconst skribilo-font-lock-keywords + (list (cons (rx "(" (group (or "document" "chapter" "code" + "section" "subsection" "subsubsection" + "prog" "p" "ref"))) + 1))) + +(defun skribilo-innermost-parens-start (state) + "Return the position of the innermost open parenthesis. STATE +is a parser state object as returned by `parse-partial-sexp'." + (elt state 1)) + +(defun skribilo-open-parens-positions (state) + "Return the positions of the currently open parentheses, +starting with the outermost. STATE is a parser state object as +returned by `parse-partial-sexp'. See \"(elisp) Parser state\"." + (elt state 9)) + +(defun skribilo-sexp-head (state) + "Return the first symbol of the innermost sexp. STATE is a +parser state object as returned by `parse-partial-sexp'." + (save-excursion + (goto-char (skribilo-innermost-parens-start state)) + (forward-char) + (intern-soft + (buffer-substring-no-properties + (point) + (progn (forward-sexp) (point)))))) + +(defun skribilo-indent-function (indent-point state) + (let ((property (get (skribilo-sexp-head state) + 'skribilo-indent-function))) + (cond + ;; If within square brackets, don't indent. + ((seq-some (lambda (position) + (eq (char-after position) + ?\[)) + (skribilo-open-parens-positions state)) + 0) + ;; Like `scheme-indent-function', but use the + ;; 'skribilo-indent-function property instead of the + ;; 'scheme-indent-function property. + ((eq property 'defun) + (lisp-indent-defform state indent-point)) + ((integerp property) + (lisp-indent-specform method state indent-point (current-column))) + ((functionp property) + (funcall property state indent-point (current-column))) + ;; Else, pass on control to `scheme-indent-function'. + (t + (scheme-indent-function indent-point state))))) + +(defun skribilo-keywords-in-sexp () + "Return the number of keywords in the sexp currently at +point. The point must be on the opening parenthesis at the +beginning of the sexp." + ;; The [] construct in skribilo isn't a proper sexp in the sense + ;; understood by `read'. So, we can't simply use `sexp-at-point' to + ;; read the whole sexp and then count the keywords. + (save-excursion + ;; TODO: What if there is whitespace after the opening + ;; parenthesis? + ;; Move into the sexp. + (forward-char) + ;; Go to the end of the first sub-sexp. + (forward-sexp) + ;; Move past one sub-sexp and increment result if that sub-sexp is + ;; a keyword. + (let ((result 0)) + (while (ignore-error 'scan-error + (or (forward-sexp) t)) + (when (keywordp (sexp-at-point)) + (setq result (1+ result)))) + result))) + +(defun skribilo-indent-form (state indent-point normal-indent) + (lisp-indent-specform + (* 2 + (save-excursion + (goto-char (skribilo-innermost-parens-start state)) + (skribilo-keywords-in-sexp))) + state indent-point normal-indent)) + +(define-minor-mode skribilo-mode + "Minor mode for editing Skribilo sources." + nil nil nil + (setq-local lisp-indent-function 'skribilo-indent-function) + (mapc (lambda (symbol) + (put symbol 'skribilo-indent-function 'skribilo-indent-form)) + '(document chapter section subsection subsubsection)) + (font-lock-add-keywords nil skribilo-font-lock-keywords) + (font-lock-flush)) + +(provide 'skribilo) |