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Pugs::Compiler::Regex(User Contributed Perl DocumentatPugs::Compiler::Regex(3)

NAME
       Pugs::Compiler::Regex - Compiler	for Perl 6 Regex

SYNOPSIS
	   use Pugs::Compiler::Regex;
	   use Pugs::Runtime::Match;

	   $regex = Pugs::Compiler::Regex->compile('a*b');
	   $match = $regex->match('aaab');
	   print $match->(), "\n";
	   print $match->from, "\n";
	   print $match->to, "\n";

	   package MyGrammar;
	   $regex = Pugs::Compiler::Regex->compile(
	       'a*', { ratchet => 1, continue => 1, sigspace =>	1 }
	   );
	   *my_match = $regex->code();
	   $match = MyGrammar->my_match('aaaa');
	   print "$match\n";

	   package MyGrammar2;
	   $regex = Pugs::Compiler::Regex->install(
	       my_match	=> 'a*',
	       { ratchet => 1, continue	=> 1, sigspace => 1 }
	   );
	   $match = MyGrammar->my_match('aaaa');
	   print "$match\n";

DESCRIPTION
       This class provides an implementation for Perl 6	regexes.  It serves as
       a base class for	Pugs::Compiler::Rule and Pugs::Compiler::Token.

METHODS
       "$regex = Pugs::Compiler::Regex->compile($str, $params);"
	   This	method acts like a constructor,	which returns a
	   Pugs::Compiler::Regex object	from the p6 regex specified in $str,
	   or throws an	exception on invalid rule syntax.

	   $params is an optional argument which specifies the following p6
	   regex modifiers:

	   "grammar => 'Pugs::Grammar::Base'"
	       Specify which namespace (Grammar) the rule belongs to.  if
	       "grammar" is not	specified, then	"Pugs::Grammar::Base" will be
	       assumed.

	   "continue =>	0"
	   "c => 0"
	       These modifiers cause the pattern to continue scanning from the
	       string's	current	"pos":

	       Note that in Perl 6 form

		   m:c/pattern/

	       is roughlh equivalent to

		   m:p/	.*? pattern /

	       Here is an example:

		   package Foo;
		   Pugs::Compiler::Regex->install(
		       word => '\w+',
		       { ratchet => 1, continue	=> 1 }
		   );
		   $s =	'hello world';
		   $match = Foo->word($s); # got 'hello'
		   $match = Foo->word($s); # got 'world'

	       XXX Note	that "continue"	or "c" currently are not supported in
	       non-ratchet mode.

	   "ratchet => 0"
	       Disable backtracking. Much faster. Defaults to 0.
	       (Pugs::Compiler::Rule and Pugs::Compiler::Token have the
	       default value of	1).

	   "pos	=> undef"
	   "p => undef"
	       Specify a string	position to match. Starts from zero.  Defaults
	       to "undef", which matches anywhere in the string.

	   "sigspace =>	0"
	       Whitespace is significant. Defaults to 0	for
	       Pugs::Compiler::Regex while 1 for Pugs::Compiler::Rule.

	   "ignorecase => 0"
	       Ignore character	case. Defaults to 0 for	Pugs::Compiler::Regex.

       "$regex->perl5()"
       "$regex->perl()"
	   Return a string holding the Perl 5 code for reconstructing the
	   current Pugs::Compiler::Regex object.

	   We are trying to make the "perl5" method does something like
	   serializing a Pugs::Compiler::Regex instance.

	   If you want the raw Perl 5 code generated by	the various emitters,
	   use "$regex->{perl5}" directly.

       "$regex->match($str, $grammar, $params)"
	   Performs matching action on $str. Note that it's a thin wrapper
	   around the p5 code compiled from the	p6 regex with run-time
	   modifier handling via the $params argument.

	   Here	is an example:

	       $regex =	Pugs::Compiler::regex->compile('a*\w');
	       my $match = $regex->match('aaa');
	       print "Capture: $match";
	       print "From: ", $match->from;
	       print "To: ", $match->to;

       "$regex->code()"
	   Returns a closure (or an anonymous sub) which does the actual
	   matching task. For example:

	     $regex = Pugs::Compiler::Regex->compile('a|b', { ratchet => 1 });
	     my	$sub = $regex->code();
	     my	$match = $sub->('MyGrammar', 'aaa');

	   Or inserts the sub into the current package:

	     package Foo;
	     $regex = Pugs::Compiler::Regex->compile('a*');
	     *match = $regex->code();
	     my	$match = __PACKAGE__->match('aaa');

	   Technically it's a thin wrapper around the "match" method.

       "$regex->install($name, @args_for_compile)"
	   Installs the	subroutine returned from the "code" method as a	named
	   subroutine using the	name specified by $name;

	   If $name is fully qualified,	then the corresponding package is
	   used, otherwise the current package is assumed.

	   @args_for_compile are those arguments fed into the "compile"
	   method.

	   It will croak if there's already a sub with the same	name exists.
	   If that's not what you want,	use the	"reinstall" method instead.

	   Here	are some examples:

	     package Bar;
	     Pugs::Compiler::Regex->install(match => 'a*', {ratchet => 1});
	     $match = Bar->match('aaa');

	     # The following line dies with the	message
	     # "Can't install regex 'match' as 'Bar::match' which already
	     # exists":
	     Pugs::Compiler::Regex->install(match => 'b*');

       "$regex->reinstall($name, @args_for_compile)"
	   Like	the "install" method but it can	replaces the named sub if it
	   already exists:

	     package Bar;
	     Pugs::Compiler::Regex->install('match', 'a*', {ratchet => 1});
	     Pugs::Compiler::Regex->reinstall('match', 'b*');
	     };
	     $match = Bar->match('bbb'); # matched here

PACKAGE	VARIABLES
       $Pugs::Compiler::Regex::NoCache
	   By default, the "compile" method will cache the compiled form (p5
	   source) of the p6 regex. The	"NoCache" variable prevents any
	   caching.

AUTHORS
       The Pugs	Team <perl6-compiler@perl.org>.

SEE ALSO
       The Perl	6 Rules	Spec:
       <http://dev.perl.org/perl6/doc/design/syn/S05.html>

COPYRIGHT
       Copyright 2006 by Flavio	Soibelmann Glock and others.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

       See <http://www.perl.com/perl/misc/Artistic.html>

perl v5.32.0			  2008-07-29	      Pugs::Compiler::Regex(3)

NAME | SYNOPSIS | DESCRIPTION | METHODS | PACKAGE VARIABLES | AUTHORS | SEE ALSO | COPYRIGHT

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