code.delx.au - gnu-emacs/blob - etc/NEWS.unicode

   1 GNU Emacs NEWS -- history of user-visible changes.
   2
   3 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
   4           Free Software Foundation, Inc.
   5 See the end of the file for license conditions.
   6
   7 Please send Emacs bug reports to bug-gnu-emacs@gnu.org.
   8 If possible, use M-x report-emacs-bug.
   9
  10 This file is about changes in the Emacs "unicode" branch.
  11
  12 Fixme: The notes about Emacs 23 are quite incomplete.
  13
  14 \f
  15 * Changes in Emacs 23.1
  16
  17 ** The Emacs character set is now a superset of Unicode.
  18 (It has about four times the code space, which should be plenty).
  19
  20 The internal encoding used for buffers and strings is now
  21 Unicode-based and called `utf-8-emacs'.  utf-8-emacs is backwards
  22 compatible with the UTF-8 encoding of Unicode.  The `emacs-mule'
  23 coding system can still read and write data in the old internal
  24 encoding.
  25
  26 There are still charsets which contain disjoint sets of characters
  27 where this is necessary or useful, especially for various Far Eastern
  28 sets which are problematic with Unicode.
  29
  30 Since the internal encoding is also used by default for byte-compiled
  31 files -- i.e. the normal coding system for byte-compiled Lisp files is
  32 now utf-8-Emacs -- Lisp containing non-ASCII characters which is
  33 compiled by Emacs 23 can't be read by earlier versions of Emacs.  Files
  34 compiled by Emacs 20, 21, or 22 are loaded correctly as emacs-mule
  35 (whether or not they contain multibyte characters), which makes loading
  36 them somewhat slower than Emacs 23-compiled files.  Thus it may be worth
  37 recompiling existing .elc files which don't need to be shared with older
  38 Emacsen.
  39
  40 ** There are assorted new coding systems/aliases -- see
  41 M-x list-coding-systems.
  42
  43 ** New charset implementation with many new charsets.
  44 See M-x list-character-sets.  New charsets can be defined conveniently
  45 as tables of unicodes.
  46
  47 The dimension of a charset is now 0, 1, 2, or 3, and the size of each
  48 dimension is no longer limited to 94 or 96.
  49
  50 Generic characters no longer exist.
  51
  52 A dynamic charset priority list is used to infer the charset of
  53 unicodes for display &c.
  54
  55 ** The following facilities are obsolete:
  56
  57 Minor modes: unify-8859-on-encoding-mode, unify-8859-on-decoding-mode
  58
  59 \f
  60 * Lisp changes in Emacs 23.1
  61
  62 map-char-table's behaviour has changed.
  63
  64 New functions: characterp, max-char, map-charset-chars,
  65 define-charset-alias, primary-charset, set-primary-charset,
  66 unify-charset, clear-charset-maps, charset-priority-list,
  67 set-charset-priority, define-coding-system,
  68 define-coding-system-alias, coding-system-aliases, langinfo,
  69 string-to-multibyte.
  70
  71 Changed functions: copy-sequence, decode-char, encode-char,
  72 set-fontset-font, new-fontset, modify-syntax-entry, define-charset,
  73 modify-category-entry
  74
  75 Obsoleted: char-bytes, chars-in-region, set-coding-priority,
  76 char-valid-p
  77
  78 \f
  79 * Incompatible Lisp changes
  80
  81 Deleted functions: make-coding-system, register-char-codings,
  82 coding-system-spec
  83
  84 ** The character codes for characters from the
  85 eight-bit-control/eight-bit-graphic charsets aren't now in the range
  86 128-255.
  87
  88
  89 \f
  90 ----------------------------------------------------------------------
  91 This file is part of GNU Emacs.
  92
  93 GNU Emacs is free software; you can redistribute it and/or modify
  94 it under the terms of the GNU General Public License as published by
  95 the Free Software Foundation; either version 2, or (at your option)
  96 any later version.
  97
  98 GNU Emacs is distributed in the hope that it will be useful,
  99 but WITHOUT ANY WARRANTY; without even the implied warranty of
 100 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 101 GNU General Public License for more details.
 102
 103 You should have received a copy of the GNU General Public License
 104 along with GNU Emacs; see the file COPYING.  If not, write to the
 105 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 106 Boston, MA 02110-1301, USA.
 107
 108 \f
 109 Local variables:
 110 mode: outline
 111 paragraph-separate: "[  \f]*$"
 112 end:
 113
 114 arch-tag: e21801b9-0724-4cda-8c07-7d60bf3db3fd