;;; mule.el --- basic commands for multilingual environment
-;; Copyright (C) 1997-2013 Free Software Foundation, Inc.
+;; Copyright (C) 1997-2014 Free Software Foundation, Inc.
;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
;; 2005, 2006, 2007, 2008, 2009, 2010, 2011
;; National Institute of Advanced Industrial Science and Technology (AIST)
;; because that makes a bootstrapping problem
;; if you need to recompile all the Lisp files using interpreted code.
-(defun charset-id (charset)
+(defun charset-id (_charset)
"Always return 0. This is provided for backward compatibility."
(declare (obsolete nil "23.1"))
0)
-(defmacro charset-bytes (charset)
+(defmacro charset-bytes (_charset)
"Always return 0. This is provided for backward compatibility."
(declare (obsolete nil "23.1"))
0)
;;; CHARACTER
(define-obsolete-function-alias 'char-valid-p 'characterp "23.1")
-(defun generic-char-p (char)
+(defun generic-char-p (_char)
"Always return nil. This is provided for backward compatibility."
(declare (obsolete nil "23.1"))
nil)
euc-tw-shift
use-roman
use-oldjis
- level-4)
+ 8-bit-level-4)
"List of symbols that control ISO-2022 encoder/decoder.
The value of the `:flags' attribute in the argument of the function
JIS0208-1983.
If `8-bit-level-4' is specified, the decoder assumes the
-implementation lavel \"4\" for 8-bit codes which means that GL is
+implementation level \"4\" for 8-bit codes which means that GL is
identified as the single-shift area. The default implementation
level for 8-bit code is \"4A\" which means that GR is identified
as the single-shift area.")
The remaining arguments must come in pairs ATTRIBUTE VALUE. ATTRIBUTE
may be any symbol.
+A coding system specifies a rule to decode (i.e. to convert a
+byte sequence to a character sequence) and a rule to encode (the
+opposite of decoding).
+
+The decoding is done by at most 3 steps; the first is to convert
+a byte sequence to a character sequence by one of Emacs'
+internal routines specified by :coding-type attribute. The
+optional second step is to convert the character sequence (the
+result of the first step) by a translation table specified
+by :decode-translation-table attribute. The optional third step
+is to convert the above reslut by a Lisp function specified
+by :post-read-conversion attribute.
+
+The encoding is done by at most 3 steps which are reverse of the
+decoding steps. The optional first step converts a character
+sequence to another character sequence by a Lisp function
+specified by :pre-write-conversion attribute. The optional
+second step converts the above result by a translation table
+specified by :encode-translation-table attribute.. The third
+step converts the abobe result to a byte sequence by one of
+Emacs' internal routines specified by :coding-type attribute.
+
The following attributes have special meanings. Those labeled as
\"(required)\" should not be omitted.
`:coding-type' (required)
-VALUE must be one of `charset', `utf-8', `utf-16', `iso-2022',
-`emacs-mule', `shift-jis', `ccl', `raw-text', `undecided'.
+VALUE specifies the format of byte sequence the coding system
+decodes and encodes to. It must be one of `charset', `utf-8',
+`utf-16', `iso-2022', `emacs-mule', `shift-jis', `ccl',
+`raw-text', `undecided'.
+
+If VALUE is `charset', the coding system is for handling a byte
+sequence in which each byte or each two to four bytes sequence
+represents a character code of a charset specified
+by :charset-list attribute.
+
+If VALUE is `utf-8', the coding system is for handling Unicode
+UTF-8 byte sequence. See also the documentation of the
+attribute :bom.
+
+If VALUE is `utf-16', the coding system is for handling Unicode
+UTF-16 byte sequence. See also the documentation of the
+attributes :bom and :endian.
+
+If VALUE is `iso-2022', the coding system is for handling a byte
+sequence conforming to ISO/IEC 2022. See also the documentation
+of the attributes :charset-list, :flags, and :designation.
+
+If VALUE is `emacs-mule', the coding system is for handling a
+byte sequence which Emacs 20 and 21 used for internal character
+representations.
+
+If VALUE is `shift-jis', the coding system is for handling a byte
+sequence of Shift_JIS format. See also the
+attribute :charset-list.
+
+If VALUE is `ccl', the coding system uses CCL programs to decodes
+and encodes to a byte sequence. The CCL programs must be
+specified by the attributes :ccl-decoder and :ccl-encoder.
+
+If VALUE is `raw-text', the coding system decodes a byte sequence
+as is.
`:eol-type'
and `mac' means Mac-like EOL \(i.e. single CR). If omitted, Emacs
detects the EOL format automatically when decoding.
-`:charset-list'
+`:charset-list' (required if :coding-type is `charset' or `shift-jis')
+
+VALUE must be a list of charsets supported by the coding system.
+
+If `coding-type:' is `charset', on decoding and encoding by the
+coding system, if a character belongs to multiple charsets in the
+list, a charset that comes earlier in the list is selected.
+
+If `:coding-type' is `iso-2022', VALUE may be `iso-2022', which
+indicates that the coding system supports all ISO-2022 based
+charsets.
+
+If `:coding-type' is `shift-jis', VALUE must be a list of three
+to four charsets supported by Shift_JIS encoding scheme. The
+first charset (one dimension) is for code space 0x00..0x7F, the
+second (one dimension) for 0xA1..0xDF, the third (two dimension)
+for 0x8140..0xEFFC, the optional fourth (thw dimension) for
+0xF040..0xFCFC.
-VALUE must be a list of charsets supported by the coding system. On
-encoding by the coding system, if a character belongs to multiple
-charsets in the list, a charset that comes earlier in the list is
-selected. If `:coding-type' is `iso-2022', VALUE may be `iso-2022',
-which indicates that the coding system supports all ISO-2022 based
-charsets. If `:coding-type' is `emacs-mule', VALUE may be
-`emacs-mule', which indicates that the coding system supports all
-charsets that have the `:emacs-mule-id' property.
+If `:coding-type' is `emacs-mule', VALUE may be `emacs-mule',
+which indicates that the coding system supports all charsets that
+have the `:emacs-mule-id' property.
`:ascii-compatible-p'
This attribute is meaningful only when `:coding-type' is `utf-16'.
-`:ccl-decoder'
+`:ccl-decoder' (required if :coding-type is `ccl')
-VALUE is a symbol representing the registered CCL program used for
-decoding. This attribute is meaningful only when `:coding-type' is
-`ccl'.
+VALUE is a CCL program name defined by `define-ccl-program'. The
+the CCL program reads a byte sequence and writes a character
+sequence as a decoding result.
-`:ccl-encoder'
+`:ccl-encoder' (required if :coding-type is `ccl')
-VALUE is a symbol representing the registered CCL program used for
-encoding. This attribute is meaningful only when `:coding-type' is
-`ccl'.
+VALUE is a CCL program name defined by `define-ccl-program'. The
+the CCL program reads a character sequence and writes a byte
+sequence as a encoding result.
`:inhibit-null-byte-detection'
(if coding-system
(setq default-terminal-coding-system coding-system))
(set-terminal-coding-system-internal coding-system terminal)
- (redraw-frame (selected-frame)))
+ (redraw-frame))
(defvar default-keyboard-coding-system nil
"Default value of the keyboard coding system.
:type '(coding-system :tag "Coding system")
:link '(info-link "(emacs)Terminal Coding")
:link '(info-link "(emacs)Unibyte Mode")
- :set (lambda (symbol value)
+ :set (lambda (_symbol value)
;; Don't load encoded-kb unnecessarily.
(if (or value (boundp 'encoded-kbd-setup-display))
(set-keyboard-coding-system value)
(head-end (+ head-start (min size 1024)))
(tail-start (+ head-start (max (- size 3072) 0)))
(tail-end (+ head-start size))
- coding-system head-found tail-found pos char-trans)
+ coding-system head-found tail-found char-trans)
;; Try a short cut by searching for the string "coding:"
;; and for "unibyte:" at the head and tail of SIZE bytes.
(setq head-found (or (search-forward "coding:" head-end t)
(let ((funcs auto-coding-functions)
(coding-system nil))
(while (and funcs (not coding-system))
- (setq coding-system (condition-case e
- (save-excursion
- (goto-char (point-min))
- (funcall (pop funcs) size))
- (error nil))))
+ (setq coding-system (ignore-errors
+ (save-excursion
+ (goto-char (point-min))
+ (funcall (pop funcs) size)))))
(if coding-system
(cons coding-system 'auto-coding-functions)))))