From 60a15fae0245e303e012408de49be87dc43af152 Mon Sep 17 00:00:00 2001 From: Lars Ingebrigtsen Date: Mon, 9 May 2022 13:38:40 +0200 Subject: [PATCH] Copy edits for the regexp sections in the manuals * doc/lispref/searching.texi (Regexp Backslash): * doc/emacs/search.texi (Regexps, Regexp Backslash): Copy edits from Jay Bingham (bug#41970). --- doc/emacs/search.texi | 56 +++++++++++++++++++------------------- doc/lispref/searching.texi | 32 +++++++++++----------- 2 files changed, 44 insertions(+), 44 deletions(-) diff --git a/doc/emacs/search.texi b/doc/emacs/search.texi index c990f5d766a..81f4d26e033 100644 --- a/doc/emacs/search.texi +++ b/doc/emacs/search.texi @@ -1027,24 +1027,9 @@ you search for @samp{a.*?$} against the text @samp{abbab} followed by a newline, it matches the whole string. Since it @emph{can} match starting at the first @samp{a}, it does. -@item @kbd{\@{@var{n}\@}} -is a postfix operator specifying @var{n} repetitions---that is, the -preceding regular expression must match exactly @var{n} times in a -row. For example, @samp{x\@{4\@}} matches the string @samp{xxxx} and -nothing else. - -@item @kbd{\@{@var{n},@var{m}\@}} -is a postfix operator specifying between @var{n} and @var{m} -repetitions---that is, the preceding regular expression must match at -least @var{n} times, but no more than @var{m} times. If @var{m} is -omitted, then there is no upper limit, but the preceding regular -expression must match at least @var{n} times.@* @samp{\@{0,1\@}} is -equivalent to @samp{?}. @* @samp{\@{0,\@}} is equivalent to -@samp{*}. @* @samp{\@{1,\@}} is equivalent to @samp{+}. - @item @kbd{[ @dots{} ]} -is a @dfn{character set}, beginning with @samp{[} and terminated by -@samp{]}. +is a @dfn{a set of alternative characters}, beginning with @samp{[} +and terminated by @samp{]}. In the simplest case, the characters between the two brackets are what this set can match. Thus, @samp{[ad]} matches either one @samp{a} or @@ -1132,12 +1117,12 @@ to depend on this behavior; it is better to quote the special character anyway, regardless of where it appears. As a @samp{\} is not special inside a character alternative, it can -never remove the special meaning of @samp{-} or @samp{]}. So you -should not quote these characters when they have no special meaning -either. This would not clarify anything, since backslashes can -legitimately precede these characters where they @emph{have} special -meaning, as in @samp{[^\]} (@code{"[^\\]"} for Lisp string syntax), -which matches any single character except a backslash. +never remove the special meaning of @samp{-}, @samp{^} or @samp{]}. +So you should not quote these characters when they have no special +meaning either. This would not clarify anything, since backslashes +can legitimately precede these characters where they @emph{have} +special meaning, as in @samp{[^\]} (@code{"[^\\]"} for Lisp string +syntax), which matches any single character except a backslash. @node Regexp Backslash @section Backslash in Regular Expressions @@ -1202,11 +1187,11 @@ matches the same text that matched the @var{d}th occurrence of a @samp{\( @dots{} \)} construct. This is called a @dfn{back reference}. -After the end of a @samp{\( @dots{} \)} construct, the matcher remembers -the beginning and end of the text matched by that construct. Then, -later on in the regular expression, you can use @samp{\} followed by the -digit @var{d} to mean ``match the same text matched the @var{d}th time -by the @samp{\( @dots{} \)} construct''. +After the end of a @samp{\( @dots{} \)} construct, the matcher +remembers the beginning and end of the text matched by that construct. +Then, later on in the regular expression, you can use @samp{\} +followed by the digit @var{d} to mean ``match the same text matched +the @var{d}th @samp{\( @dots{} \)} construct''. The strings matching the first nine @samp{\( @dots{} \)} constructs appearing in a regular expression are assigned numbers 1 through 9 in @@ -1223,6 +1208,21 @@ If a particular @samp{\( @dots{} \)} construct matches more than once (which can easily happen if it is followed by @samp{*}), only the last match is recorded. +@item @kbd{\@{@var{m}\@}} +is a postfix operator specifying @var{m} repetitions---that is, the +preceding regular expression must match exactly @var{m} times in a +row. For example, @samp{x\@{4\@}} matches the string @samp{xxxx} and +nothing else. + +@item @kbd{\@{@var{m},@var{n}\@}} +is a postfix operator specifying between @var{m} and @var{n} +repetitions---that is, the preceding regular expression must match at +least @var{m} times, but no more than @var{n} times. If @var{n} is +omitted, then there is no upper limit, but the preceding regular +expression must match at least @var{m} times.@* @samp{\@{0,1\@}} is +equivalent to @samp{?}. @* @samp{\@{0,\@}} is equivalent to +@samp{*}. @* @samp{\@{1,\@}} is equivalent to @samp{+}. + @item \` matches the empty string, but only at the beginning of the string or buffer (or its accessible portion) being matched against. diff --git a/doc/lispref/searching.texi b/doc/lispref/searching.texi index c9828f9c868..976f8b4b4bd 100644 --- a/doc/lispref/searching.texi +++ b/doc/lispref/searching.texi @@ -549,12 +549,12 @@ can act. It is poor practice to depend on this behavior; quote the special character anyway, regardless of where it appears. As a @samp{\} is not special inside a character alternative, it can -never remove the special meaning of @samp{-} or @samp{]}. So you -should not quote these characters when they have no special meaning -either. This would not clarify anything, since backslashes can -legitimately precede these characters where they @emph{have} special -meaning, as in @samp{[^\]} (@code{"[^\\]"} for Lisp string syntax), -which matches any single character except a backslash. +never remove the special meaning of @samp{-}, @samp{^} or @samp{]}. +So you should not quote these characters when they have no special +meaning either. This would not clarify anything, since backslashes +can legitimately precede these characters where they @emph{have} +special meaning, as in @samp{[^\]} (@code{"[^\\]"} for Lisp string +syntax), which matches any single character except a backslash. In practice, most @samp{]} that occur in regular expressions close a character alternative and hence are special. However, occasionally a @@ -823,21 +823,21 @@ the characters that stand for them. matches any character whose syntax is not @var{code}. @cindex category, regexp search for -@item \c@var{c} -matches any character whose category is @var{c}. Here @var{c} is a -character that represents a category: thus, @samp{c} for Chinese -characters or @samp{g} for Greek characters in the standard category -table. You can see the list of all the currently defined categories -with @kbd{M-x describe-categories @key{RET}}. You can also define -your own categories in addition to the standard ones using the +@item \c@var{code} +matches any character whose category is @var{code}. Here @var{code} +is a character that represents a category: thus, @samp{code} for +Chinese characters or @samp{g} for Greek characters in the standard +category table. You can see the list of all the currently defined +categories with @kbd{M-x describe-categories @key{RET}}. You can also +define your own categories in addition to the standard ones using the @code{define-category} function (@pxref{Categories}). -@item \C@var{c} -matches any character whose category is not @var{c}. +@item \C@var{code} +matches any character whose category is not @var{code}. @end table The following regular expression constructs match the empty string---that is, -they don't use up any characters---but whether they match depends on the +they don't consume any characters---but whether they match depends on the context. For all, the beginning and end of the accessible portion of the buffer are treated as if they were the actual beginning and end of the buffer. -- 2.39.2