xemacs-beta: man/lispref/searching.texi comparison

comparison man/lispref/searching.texi @ 316:512e409c26a2 r21-0b56

Import from CVS: tag r21-0b56

author	cvs
date	Mon, 13 Aug 2007 10:44:46 +0200
parents	341dac730539
children	a4f53d9b3154

comparison

equal deleted inserted replaced

-:5e87bc5b1ee4
+:512e409c26a2
 @c Did perl get this from somewhere?  What's the real history of *? ?
 This construct is very useful for when you want to match the text inside
 a pair of delimiters.  For instance, @samp{/\*.*?\*/} will match C
 comments in a string.  This could not be so elegantly achieved without
-the use of a nongreedy quantifier.
+the use of a non-greedy quantifier.
 This construct has not been available prior to XEmacs 20.4.  It is not
 available in FSF Emacs.
 @item +?
 substring to be recorded for future reference.
 This is useful when you need to use a lot of nested grouping @samp{\(
 @dots{} \)} constructs to express complex alternation, but only want to
 memoize, or capture, one or two of the subexpression matches.  Since
-@samp{\(?: @dots{} \)} doesn't capture a submatch, it also doesn't need
+@samp{\(?: @dots{} \)} doesn't capture a sub-match, it also doesn't need
 to be counted when you count @samp{\( @dots{} \)} groups to figure the
 @samp{match-string} index.  That turns out to be a very convenient
 characteristic.
-This situtation occurs where parts of a regular expression have been
+This situation occurs where parts of a regular expression have been
 automaticly generated by a program that builds them from lists of
 strings, and the static code following the matching operation must
-access a specific match number.  Here's an example that shows this:
+access a specific match number.  Here's an example that shows this.
-@example
+We will assume that @code{(require 'regexp-opt)} has been executed
-@group
+already, to ensure that @file{regexp-opt.el}, which is part of the
-;; Assume that:
+@code{xemacs-devel} package, is loaded.
-(require 'regexp-opt) ;; gets executed at toplevel
+@ifinfo
-;;; `regexp-opt.el' is part of the "xemacs-devel" package.
+Please evaluate that @code{require} expression now, using @kbd{C-x C-e},
-;; ... and that VARNAMES is a list of strings holding the name of some
+if you intend to try the following example.
-;; variables extracted from the program source you are editting and
+@end ifinfo
-;; running this function on.  For this example, it will just be bound
+In a real program, lets pretend that @var{varnames} would be a list of
-;; in the let* expression.
+strings holding the names of some variables extracted somehow from the
+text of a program source you are editing and running this function on.
+For the purposes of this illustration, we can just bind it in the
+@code{let*} expression.
+@example
+@group
 (let* ((varnames '("k" "n" "i" "j" "varname"))
 (keys-regexp (regexp-opt
-		     (mapcar #'symbol-name
+(mapcar #'symbol-name
-			     '(if then else elif
+'(if then else elif
-			       case in of do while
+case in of do while
-			       with for next unless
+with for next unless
-			       cond begin end))))
+cond begin end))))
 (varname-regexp (regexp-opt varnames))
 (contrived-regexp (concat "\\(" keys-regexp "\\)"
-				"\\s-(\\s-\\("
+"\\s-(\\s-\\("
-				varname-regexp
+varname-regexp
-				"\\)\\s-)"))
+"\\)\\s-)"))
 (keyname "")
 (varname ""))
-;; In the body of this particular defun, we:
+;; @r{In the body of this particular defun, we:}
 (re-search-forward contrived-regexp nil t)
-;; ... and it finds a match.  Now we want to extract the text that
+;; @r{@dots{} and it finds a match.  Now we want to extract the}
-;; it matched on, and save it into KEYNAME and VARNAME.
+;; @r{text that it matched on, and save it into @code{keyname}}
+;; @r{and @code{varname}.}
 (setq keyname (match-string 1)
-	varname (match-string 2))
+varname (match-string 2))
-;; ... and then do something with those values.
+;; @r{@dots{} and then do something with those values.}
 (list keyname varname))
-;; Here's something for it to match, so you can try it with `C-x C-e'.
+;; @r{Here's something for it to match, so you can try it with}
+;; @kbd{C-x C-e}
 ;; while ( j ) do ...
 @end group
 @end example
-Here you can see that if the regular expression returned by
+Here you should see that if the regular expression returned by
-@samp{regexp-opt} did not use @samp{\(?: @dots{} \)} for grouping, and
+@code{regexp-opt} did not use @samp{\(?: @dots{} \)} for grouping, and
 instead used @samp{\( @dots{} \)}, it would be necessary to count the
-number of opening parentheses in the @samp{keys-regexp} and to use that
+number of opening parentheses in the @code{keys-regexp} and to use that
 figure to calculate which match number is matched by the
-@code{varname-regexp}.  It is much more convienient to be able to just
+@code{varname-regexp}.  It is much more convenient to be able to just
 ask for the second match string.
 @c This is used to good advantage by the font-locking code....
 @c ... It will be.  It's not yet, but will be.
 This function returns the position of the start of text matched by the
 last regular expression searched for, or a subexpression of it.
 If @var{count} is zero, then the value is the position of the start of
 the entire match.  Otherwise, @var{count} specifies a subexpression in
-the regular expresion, and the value of the function is the starting
+the regular expression, and the value of the function is the starting
 position of the match for that subexpression.
 The value is @code{nil} for a subexpression inside a @samp{\|}
 alternative that wasn't used in the match.
 @end defun

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comparison man/lispref/searching.texi @ 316:512e409c26a2 r21-0b56