lisp/case-table.el

   1 ;;; case-table.el --- code to extend the character set and support case tables
   2
   3 ;; Copyright (C) 1988, 1994, 2005 Free Software Foundation, Inc.
   4
   5 ;; Author: Howard Gayle
   6 ;; Maintainer: FSF
   7 ;; Keywords: i18n
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; Written by:
  29 ;; TN/ETX/TX/UMG Howard Gayle        UUCP : seismo!enea!erix!howard
  30 ;; Telefonaktiebolaget L M Ericsson  Phone: +46 8 719 55 65
  31 ;; Ericsson Telecom                  Telex: 14910 ERIC S
  32 ;; S-126 25 Stockholm                FAX  : +46 8 719 64 82
  33 ;; Sweden
  34
  35 ;;; Code:
  36
  37 (defvar set-case-syntax-offset 0)
  38
  39 (defvar set-case-syntax-set-multibyte nil)
  40
  41 (defun describe-buffer-case-table ()
  42   "Describe the case table of the current buffer."
  43   (interactive)
  44   (let ((description (make-char-table 'case-table)))
  45     (map-char-table
  46      (function (lambda (key value)
  47                  (aset
  48                   description key
  49                   (cond ((not (natnump value))
  50                          "case-invariant")
  51                         ((/= key (downcase key))
  52                          (concat "uppercase, matches "
  53                                  (char-to-string (downcase key))))
  54                         ((/= key (upcase key))
  55                          (concat "lowercase, matches "
  56                                  (char-to-string (upcase key))))
  57                         (t "case-invariant")))))
  58      (current-case-table))
  59     (save-excursion
  60      (with-output-to-temp-buffer "*Help*"
  61        (set-buffer standard-output)
  62        (describe-vector description)
  63        (help-mode)))))
  64
  65 (defun get-upcase-table (case-table)
  66   "Return the upcase table of CASE-TABLE."
  67   (or (char-table-extra-slot case-table 0)
  68       ;; Setup all extra slots of CASE-TABLE by temporarily selecting
  69       ;; it as the standard case table.
  70       (let ((old (standard-case-table)))
  71         (unwind-protect
  72             (progn
  73               (set-standard-case-table case-table)
  74               (char-table-extra-slot case-table 0))
  75           (or (eq case-table old)
  76               (set-standard-case-table old))))))
  77
  78 (defun copy-case-table (case-table)
  79   (let ((copy (copy-sequence case-table))
  80         (up (char-table-extra-slot case-table 0)))
  81     ;; Clear out the extra slots (except for upcase table) so that
  82     ;; they will be recomputed from the main (downcase) table.
  83     (if up
  84         (set-char-table-extra-slot copy 0 (copy-sequence up)))
  85     (set-char-table-extra-slot copy 1 nil)
  86     (set-char-table-extra-slot copy 2 nil)
  87     copy))
  88
  89 (defsubst set-case-syntax-1 (char)
  90   "Offset CHAR by `set-case-syntax-offset' if CHAR is a non-ASCII 8-bit char."
  91   (if (and (>= char 128) (< char 256))
  92       (+ char set-case-syntax-offset)
  93     char))
  94
  95 (defun set-case-syntax-delims (l r table)
  96   "Make characters L and R a matching pair of non-case-converting delimiters.
  97 This sets the entries for L and R in TABLE, which is a string
  98 that will be used as the downcase part of a case table.
  99 It also modifies `standard-syntax-table' to
 100 indicate left and right delimiters."
 101   (setq l (set-case-syntax-1 l))
 102   (setq r (set-case-syntax-1 r))
 103   (aset table l l)
 104   (aset table r r)
 105   (let ((up (get-upcase-table table)))
 106     (aset up l l)
 107     (aset up r r))
 108   ;; Clear out the extra slots so that they will be
 109   ;; recomputed from the main (downcase) table and upcase table.
 110   (set-char-table-extra-slot table 1 nil)
 111   (set-char-table-extra-slot table 2 nil)
 112   (modify-syntax-entry l (concat "(" (char-to-string r) "  ")
 113                        (standard-syntax-table))
 114   (modify-syntax-entry r (concat ")" (char-to-string l) "  ")
 115                        (standard-syntax-table)))
 116
 117 (defun set-case-syntax-pair (uc lc table)
 118   "Make characters UC and LC a pair of inter-case-converting letters.
 119 This sets the entries for characters UC and LC in TABLE, which is a string
 120 that will be used as the downcase part of a case table.
 121 It also modifies `standard-syntax-table' to give them the syntax of
 122 word constituents."
 123   (setq uc (set-case-syntax-1 uc))
 124   (setq lc (set-case-syntax-1 lc))
 125   (aset table uc lc)
 126   (aset table lc lc)
 127   (let ((up (get-upcase-table table)))
 128     (aset up uc uc)
 129     (aset up lc uc))
 130   ;; Clear out the extra slots so that they will be
 131   ;; recomputed from the main (downcase) table and upcase table.
 132   (set-char-table-extra-slot table 1 nil)
 133   (set-char-table-extra-slot table 2 nil)
 134   (modify-syntax-entry lc "w   " (standard-syntax-table))
 135   (modify-syntax-entry uc "w   " (standard-syntax-table)))
 136
 137 (defun set-upcase-syntax (uc lc table)
 138   "Make character UC an upcase of character LC.
 139 It also modifies `standard-syntax-table' to give them the syntax of
 140 word constituents."
 141   (setq uc (set-case-syntax-1 uc))
 142   (setq lc (set-case-syntax-1 lc))
 143   (aset table lc lc)
 144   (let ((up (get-upcase-table table)))
 145     (aset up uc uc)
 146     (aset up lc uc))
 147   ;; Clear out the extra slots so that they will be
 148   ;; recomputed from the main (downcase) table and upcase table.
 149   (set-char-table-extra-slot table 1 nil)
 150   (set-char-table-extra-slot table 2 nil)
 151   (modify-syntax-entry lc "w   " (standard-syntax-table))
 152   (modify-syntax-entry uc "w   " (standard-syntax-table)))
 153
 154 (defun set-downcase-syntax (uc lc table)
 155   "Make character LC a downcase of character UC.
 156 It also modifies `standard-syntax-table' to give them the syntax of
 157 word constituents."
 158   (setq uc (set-case-syntax-1 uc))
 159   (setq lc (set-case-syntax-1 lc))
 160   (aset table uc lc)
 161   (aset table lc lc)
 162   (let ((up (get-upcase-table table)))
 163     (aset up uc uc))
 164   ;; Clear out the extra slots so that they will be
 165   ;; recomputed from the main (downcase) table and upcase table.
 166   (set-char-table-extra-slot table 1 nil)
 167   (set-char-table-extra-slot table 2 nil)
 168   (modify-syntax-entry lc "w   " (standard-syntax-table))
 169   (modify-syntax-entry uc "w   " (standard-syntax-table)))
 170
 171 (defun set-case-syntax (c syntax table)
 172   "Make character C case-invariant with syntax SYNTAX.
 173 This sets the entry for character C in TABLE, which is a string
 174 that will be used as the downcase part of a case table.
 175 It also modifies `standard-syntax-table'.
 176 SYNTAX should be \" \", \"w\", \".\" or \"_\"."
 177   (setq c (set-case-syntax-1 c))
 178   (aset table c c)
 179   (let ((up (get-upcase-table table)))
 180     (aset up c c))
 181   ;; Clear out the extra slots so that they will be
 182   ;; recomputed from the main (downcase) table and upcase table.
 183   (set-char-table-extra-slot table 1 nil)
 184   (set-char-table-extra-slot table 2 nil)
 185   (modify-syntax-entry c syntax (standard-syntax-table)))
 186
 187 (provide 'case-table)
 188
 189 ;;; arch-tag: 3c2cf885-2c9a-449a-9972-2e269191896d
 190 ;;; case-table.el ends here