1 ;;; flow-fill.el --- interprete RFC2646 "flowed" text
2 ;; Copyright (C) 2000 Free Software Foundation, Inc.
4 ;; Author: Simon Josefsson <jas@pdc.kth.se>
7 ;; This program is free software; you can redistribute it and/or modify
8 ;; it under the terms of the GNU General Public License as published by
9 ;; the Free Software Foundation; either version 2 of the License, or
10 ;; (at your option) any later version.
12 ;; This program is distributed in the hope that it will be useful,
13 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
14 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 ;; GNU General Public License for more details.
17 ;; You should have received a copy of the GNU General Public License
18 ;; along with this program; if not, write to the Free Software
19 ;; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 ;; This implement decoding of RFC2646 formatted text, including the
24 ;; quoted-depth wins rules.
26 ;; Theory of operation: search for lines ending with SPC, save quote
27 ;; length of line, remove SPC and concatenate line with the following
28 ;; line if quote length of following line matches current line.
30 ;; When no further concatenations are possible, we've found a
31 ;; paragraph and we let `fill-region' fill the long line into several
32 ;; lines with the quote prefix as `fill-prefix'.
34 ;; Todo: encoding, implement basic `fill-region' (Emacs and XEmacs
35 ;; implementations differ..)
39 ;; 2000-02-17 posted on ding mailing list
40 ;; 2000-02-19 use `point-at-{b,e}ol' in XEmacs
41 ;; 2000-03-11 no compile warnings for point-at-bol stuff
42 ;; 2000-03-26 commited to gnus cvs
43 ;; 2000-10-23 don't flow "-- " lines, make "quote-depth wins" rule
44 ;; work when first line is at level 0.
48 (eval-when-compile (require 'cl))
51 (defalias 'fill-flowed-point-at-bol
52 (if (fboundp 'point-at-bol)
54 'line-beginning-position))
56 (defalias 'fill-flowed-point-at-eol
57 (if (fboundp 'point-at-eol)
61 (defun fill-flowed (&optional buffer)
63 (set-buffer (or (current-buffer) buffer))
64 (goto-char (point-min))
65 (while (re-search-forward " $" nil t)
68 (looking-at "^\\(>*\\)\\( ?\\)"))
69 (let ((quote (match-string 1)) sig)
70 (if (string= quote "")
72 (when (and quote (string= (match-string 2) ""))
74 ;; insert SP after quote for pleasant reading of quoted lines
76 (when (> (skip-chars-forward ">") 0)
78 (while (and (save-excursion
79 (ignore-errors (backward-char 3))
80 (setq sig (looking-at "-- "))
81 (looking-at "[^-][^-] "))
85 (looking-at (format "^\\(%s\\)\\([^>]\\)" (or quote " ?"))))))
87 (replace-match (if (string= (match-string 2) " ")
89 (backward-delete-char -1)
92 (let ((fill-prefix (when quote (concat quote " "))))
93 (fill-region (fill-flowed-point-at-bol)
94 (fill-flowed-point-at-eol)
95 'left 'nosqueeze))))))))
99 ;;; flow-fill.el ends here