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(Character Codes): Remove obsolete function char-valid-p, and document

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characterp instead.
This commit is contained in:
Chong Yidong 2008-10-22 19:37:07 +00:00
parent f0143c43d4
commit ffdbc44b56
1 changed files with 18 additions and 19 deletions
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doc/lispref/nonascii.texi
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@ -289,32 +289,31 @@ or @code{eight-bit-graphic}.
@section Character Codes
@cindex character codes
The unibyte and multibyte text representations use different character
codes. The valid character codes for unibyte representation range from
0 to 255---the values that can fit in one byte. The valid character
codes for multibyte representation range from 0 to 524287, but not all
values in that range are valid. The values 128 through 255 are not
entirely proper in multibyte text, but they can occur if you do explicit
encoding and decoding (@pxref{Explicit Encoding}). Some other character
codes cannot occur at all in multibyte text. Only the @acronym{ASCII} codes
0 through 127 are completely legitimate in both representations.
The unibyte and multibyte text representations use different
character codes. The valid character codes for unibyte representation
range from 0 to 255---the values that can fit in one byte. The valid
character codes for multibyte representation range from 0 to 4194303,
but not all values in that range are valid. The values 128 through
255 do not usually show up in multibyte text, but they can occur if
you do explicit encoding and decoding (@pxref{Explicit Encoding}).
Some other character codes cannot occur at all in multibyte text.
Only the @acronym{ASCII} codes 0 through 127 are completely legitimate
in both representations.
@defun char-valid-p charcode &optional genericp
This returns @code{t} if @var{charcode} is valid (either for unibyte
text or for multibyte text).
@defun characterp charcode
This returns @code{t} if @var{charcode} is a valid character, and
@code{nil} otherwise.
@example
(char-valid-p 65)
(characterp 65)
@result{} t
(char-valid-p 256)
(characterp 256)
@result{} nil
(char-valid-p 2248)
(characterp 4194303)
@result{} t
(characterp 4194304)
@result{} nil
@end example
If the optional argument @var{genericp} is non-@code{nil}, this
function also returns @code{t} if @var{charcode} is a generic
character (@pxref{Splitting Characters}).
@end defun
@node Character Sets