Commit 8f17d892 authored by Richard M. Stallman's avatar Richard M. Stallman
Browse files

Use Lisp escape sequences only inside string syntax.

parent 65569e52
......@@ -311,11 +311,14 @@ matches both @samp{]} and @samp{-}.
To include @samp{^} in a character alternative, put it anywhere but at
the beginning.
The beginning and end of a range of multibyte characters must be in the
same character set (@pxref{Character Sets}). Thus, @samp{[\x8e0-\x97c]}
is invalid because character 0x8e0 (@samp{a} with grave accent) is in
the Emacs character set for Latin-1 but the character 0x97c (@samp{u}
with diaeresis) is in the Emacs character set for Latin-2.
The beginning and end of a range of multibyte characters must be in
the same character set (@pxref{Character Sets}). Thus,
@code{"[\x8e0-\x97c]"} is invalid because character 0x8e0 (@samp{a}
with grave accent) is in the Emacs character set for Latin-1 but the
character 0x97c (@samp{u} with diaeresis) is in the Emacs character
set for Latin-2. (We use Lisp string syntax to write that example,
and a few others in the next few paragraphs, in order to include hex
escape sequences in them.)
If a range starts with a unibyte character @var{c} and ends with a
multibyte character @var{c2}, the range is divided into two parts: one
......@@ -324,10 +327,10 @@ is @samp{@var{c}..?\377}, the other is @samp{@var{c1}..@var{c2}}, where
belongs.
You cannot always match all non-@sc{ascii} characters with the regular
expression @samp{[\200-\377]}. This works when searching a unibyte
expression @code{"[\200-\377]"}. This works when searching a unibyte
buffer or string (@pxref{Text Representations}), but not in a multibyte
buffer or string, because many non-@sc{ascii} characters have codes
above octal 0377. However, the regular expression @samp{[^\000-\177]}
above octal 0377. However, the regular expression @code{"[^\000-\177]"}
does match all non-@sc{ascii} characters (see below regarding @samp{^}),
in both multibyte and unibyte representations, because only the
@sc{ascii} characters are excluded.
......@@ -361,7 +364,7 @@ match anything. Thus, @samp{^foo} matches a @samp{foo} that occurs at
the beginning of a line.
When matching a string instead of a buffer, @samp{^} matches at the
beginning of the string or after a newline character @samp{\n}.
beginning of the string or after a newline character.
For historical compatibility reasons, @samp{^} can be used only at the
beginning of the regular expression, or after @samp{\(} or @samp{\|}.
......@@ -373,7 +376,7 @@ is similar to @samp{^} but matches only at the end of a line. Thus,
@samp{x+$} matches a string of one @samp{x} or more at the end of a line.
When matching a string instead of a buffer, @samp{$} matches at the end
of the string or before a newline character @samp{\n}.
of the string or before a newline character.
For historical compatibility reasons, @samp{$} can be used only at the
end of the regular expression, or before @samp{\)} or @samp{\|}.
......
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