lisp/case-table.el

   1 ;;; case-table.el --- code to extend the character set and support case tables
   2
   3 ;; Copyright (C) 1988, 1994, 2002, 2003, 2004,
   4 ;;   2005 Free Software Foundation, Inc.
   5
   6 ;; Author: Howard Gayle
   7 ;; Maintainer: FSF
   8 ;; Keywords: i18n
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; Written by:
  30 ;; TN/ETX/TX/UMG Howard Gayle        UUCP : seismo!enea!erix!howard
  31 ;; Telefonaktiebolaget L M Ericsson  Phone: +46 8 719 55 65
  32 ;; Ericsson Telecom                  Telex: 14910 ERIC S
  33 ;; S-126 25 Stockholm                FAX  : +46 8 719 64 82
  34 ;; Sweden
  35
  36 ;;; Code:
  37
  38 (defvar set-case-syntax-offset 0)
  39
  40 (defvar set-case-syntax-set-multibyte nil)
  41
  42 (defun describe-buffer-case-table ()
  43   "Describe the case table of the current buffer."
  44   (interactive)
  45   (let ((description (make-char-table 'case-table)))
  46     (map-char-table
  47      (function (lambda (key value)
  48                  (aset
  49                   description key
  50                   (cond ((not (natnump value))
  51                          "case-invariant")
  52                         ((/= key (downcase key))
  53                          (concat "uppercase, matches "
  54                                  (char-to-string (downcase key))))
  55                         ((/= key (upcase key))
  56                          (concat "lowercase, matches "
  57                                  (char-to-string (upcase key))))
  58                         (t "case-invariant")))))
  59      (current-case-table))
  60     (save-excursion
  61      (with-output-to-temp-buffer "*Help*"
  62        (set-buffer standard-output)
  63        (describe-vector description)
  64        (help-mode)))))
  65
  66 (defun get-upcase-table (case-table)
  67   "Return the upcase table of CASE-TABLE."
  68   (or (char-table-extra-slot case-table 0)
  69       ;; Setup all extra slots of CASE-TABLE by temporarily selecting
  70       ;; it as the standard case table.
  71       (let ((old (standard-case-table)))
  72         (unwind-protect
  73             (progn
  74               (set-standard-case-table case-table)
  75               (char-table-extra-slot case-table 0))
  76           (or (eq case-table old)
  77               (set-standard-case-table old))))))
  78
  79 (defun copy-case-table (case-table)
  80   (let ((copy (copy-sequence case-table))
  81         (up (char-table-extra-slot case-table 0)))
  82     ;; Clear out the extra slots (except for upcase table) so that
  83     ;; they will be recomputed from the main (downcase) table.
  84     (if up
  85         (set-char-table-extra-slot copy 0 (copy-sequence up)))
  86     (set-char-table-extra-slot copy 1 nil)
  87     (set-char-table-extra-slot copy 2 nil)
  88     copy))
  89
  90 (defsubst set-case-syntax-1 (char)
  91   "Offset CHAR by `set-case-syntax-offset' if CHAR is a non-ASCII 8-bit char."
  92   (if (and (>= char 128) (< char 256))
  93       (+ char set-case-syntax-offset)
  94     char))
  95
  96 (defun set-case-syntax-delims (l r table)
  97   "Make characters L and R a matching pair of non-case-converting delimiters.
  98 This sets the entries for L and R in TABLE, which is a string
  99 that will be used as the downcase part of a case table.
 100 It also modifies `standard-syntax-table' to
 101 indicate left and right delimiters."
 102   (setq l (set-case-syntax-1 l))
 103   (setq r (set-case-syntax-1 r))
 104   (aset table l l)
 105   (aset table r r)
 106   (let ((up (get-upcase-table table)))
 107     (aset up l l)
 108     (aset up r r))
 109   ;; Clear out the extra slots so that they will be
 110   ;; recomputed from the main (downcase) table and upcase table.
 111   (set-char-table-extra-slot table 1 nil)
 112   (set-char-table-extra-slot table 2 nil)
 113   (modify-syntax-entry l (concat "(" (char-to-string r) "  ")
 114                        (standard-syntax-table))
 115   (modify-syntax-entry r (concat ")" (char-to-string l) "  ")
 116                        (standard-syntax-table)))
 117
 118 (defun set-case-syntax-pair (uc lc table)
 119   "Make characters UC and LC a pair of inter-case-converting letters.
 120 This sets the entries for characters UC and LC in TABLE, which is a string
 121 that will be used as the downcase part of a case table.
 122 It also modifies `standard-syntax-table' to give them the syntax of
 123 word constituents."
 124   (setq uc (set-case-syntax-1 uc))
 125   (setq lc (set-case-syntax-1 lc))
 126   (aset table uc lc)
 127   (aset table lc lc)
 128   (let ((up (get-upcase-table table)))
 129     (aset up uc uc)
 130     (aset up lc uc))
 131   ;; Clear out the extra slots so that they will be
 132   ;; recomputed from the main (downcase) table and upcase table.
 133   (set-char-table-extra-slot table 1 nil)
 134   (set-char-table-extra-slot table 2 nil)
 135   (modify-syntax-entry lc "w   " (standard-syntax-table))
 136   (modify-syntax-entry uc "w   " (standard-syntax-table)))
 137
 138 (defun set-upcase-syntax (uc lc table)
 139   "Make character UC an upcase of character LC.
 140 It also modifies `standard-syntax-table' to give them the syntax of
 141 word constituents."
 142   (setq uc (set-case-syntax-1 uc))
 143   (setq lc (set-case-syntax-1 lc))
 144   (aset table lc lc)
 145   (let ((up (get-upcase-table table)))
 146     (aset up uc uc)
 147     (aset up lc uc))
 148   ;; Clear out the extra slots so that they will be
 149   ;; recomputed from the main (downcase) table and upcase table.
 150   (set-char-table-extra-slot table 1 nil)
 151   (set-char-table-extra-slot table 2 nil)
 152   (modify-syntax-entry lc "w   " (standard-syntax-table))
 153   (modify-syntax-entry uc "w   " (standard-syntax-table)))
 154
 155 (defun set-downcase-syntax (uc lc table)
 156   "Make character LC a downcase of character UC.
 157 It also modifies `standard-syntax-table' to give them the syntax of
 158 word constituents."
 159   (setq uc (set-case-syntax-1 uc))
 160   (setq lc (set-case-syntax-1 lc))
 161   (aset table uc lc)
 162   (aset table lc lc)
 163   (let ((up (get-upcase-table table)))
 164     (aset up uc uc))
 165   ;; Clear out the extra slots so that they will be
 166   ;; recomputed from the main (downcase) table and upcase table.
 167   (set-char-table-extra-slot table 1 nil)
 168   (set-char-table-extra-slot table 2 nil)
 169   (modify-syntax-entry lc "w   " (standard-syntax-table))
 170   (modify-syntax-entry uc "w   " (standard-syntax-table)))
 171
 172 (defun set-case-syntax (c syntax table)
 173   "Make character C case-invariant with syntax SYNTAX.
 174 This sets the entry for character C in TABLE, which is a string
 175 that will be used as the downcase part of a case table.
 176 It also modifies `standard-syntax-table'.
 177 SYNTAX should be \" \", \"w\", \".\" or \"_\"."
 178   (setq c (set-case-syntax-1 c))
 179   (aset table c c)
 180   (let ((up (get-upcase-table table)))
 181     (aset up c c))
 182   ;; Clear out the extra slots so that they will be
 183   ;; recomputed from the main (downcase) table and upcase table.
 184   (set-char-table-extra-slot table 1 nil)
 185   (set-char-table-extra-slot table 2 nil)
 186   (modify-syntax-entry c syntax (standard-syntax-table)))
 187
 188 (provide 'case-table)
 189
 190 ;;; arch-tag: 3c2cf885-2c9a-449a-9972-2e269191896d
 191 ;;; case-table.el ends here