NAME

Pugs::Compiler::Rule - Compiler for Perl 6 Rules

SYNOPSIS

use Pugs::Compiler::Rule;

my $rule = Pugs::Compiler::Rule->compile( '((.).).' );
my $match = $rule->match( 'abc' );

if ($match) {               # true
    print $match;           # "abc"
    print $match->from;     # 0
    print $match->to;       # 3
    print $match->[0];      # "ab"
    print $match->[0][0];   # "a"
}

DESCRIPTION

This module provides an implementation for Perl 6 Rules. It is a front-end to several other modules:

• Pugs::Grammar::Rule parses the Rules syntax.

• Pugs::Grammar::Rule::Rule specifies the Rules syntax with Rules.

• Pugs::Emitter::Rule::Perl5 converts parsed Rules to Perl 5 code.

• Pugs::Runtime::Rule provides the runtime engine for Rules.

• Pugs::Runtime::Match represents a Match object.

Implemented Features

. ? * + *? +? ??
\char <ws> <word> literal
$variable @variable
<'literal'>
[] 
()     
<subrule>
<namespace::subrule>
<?subrule>
<!subrule>
|
<@var>             -- special-cased for array-of-rule (but not Rule|Str)
{code}             -- non-capturing closure
                   -- perl5 syntax inside closure
                   -- $/ doesn't work yet
{ return code }    -- capturing closure
                   -- perl5 syntax inside closure
                   -- $/ works
$var := (capture)  -- capture aliasing
$<> $/<>           -- special variables can't be used inside a match yet
$/ 
$<0> $<1>
<$var>             -- untested

Unimplemented Features

$/<0> $/<1>
$/0 $/1
$0 $1
<"literal">
^ ^^ $ $$
<unicode-class> <+unicode-class> <+unicode-class+unicode-class>
<&var> 
<%var>
**{n..m}
: :: :::   (commit)
$var := [non-capture]
$var := <rule>
<(closure-assertion)> <{code-returns-rule}>
<<character-class>> <[character-class]>
:flag :flag() :flag[]
lookahead lookbehind
#comment\n
\x0a \0123 ...
<?ws>                      -- optional whitespace ???
&    
<!abc>                     -- is this !<abc> or !abc ?
\n \N

METHODS

compile (Str $rule_source)

Class method. Returns a compiled rule object, or throws an exception on invalid rule syntax.

match (Str $match_against)

Instance method. Returns a Pugs::Runtime::Match object.

CAVEATS

This is an experimental development version. There are currently no support for match flags, and the API is still in flux.

It is currently unsuitable for just about any use other than Pugs development. Please join us on irc.freenode.net #perl6 if you'd like to participate. :-)

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