NAME

       Kavorka - function signatures with the lure of the animal

SYNOPSIS

          use Kavorka;

          fun maxnum (Num @numbers) {
             my $max = shift @numbers;
             for (@numbers) {
                $max = $_ if $max < $_;
             }
             return $max;
          }

          my $biggest = maxnum(42, 3.14159, 666);

STATUS

       Kavorka is still at a very early stage of development; there are likely to be many bugs
       that still need to be shaken out. Certain syntax features are a little odd and may need to
       be changed in incompatible ways.

DESCRIPTION

       Kavorka provides "fun" and "method" keywords for declaring functions and methods. It uses
       Perl 5.14's keyword API, so should work more reliably than source filters or
       Devel::Declare-based modules.

       The syntax provided by Kavorka is largely inspired by Perl 6, though it has also been
       greatly influenced by Method::Signatures and Function::Parameters.

       For information using the keywords exported by Kavorka:

       •   Kavorka::Manual::Functions

       •   Kavorka::Manual::Methods

       •   Kavorka::Manual::MethodModifiers

       •   Kavorka::Manual::MultiSubs

   Exports
       "-default"
           Exports "fun" and "method".

       "-modifiers"
           Exports "before", "after", and "around".

       "-allmodifiers"
           Exports "before", "after", "around", "augment", and "override".

       "-all"
           Exports "fun", "method", "before", "after", "around", "augment", "override",
           "classmethod", "objectmethod", and "multi".

       For example:

          # Everything except objectmethod and multi...
          use Kavorka qw( -default -allmodifiers classmethod );

       You can rename imported functions:

          use Kavorka method => { -as => 'meth' };

       You can provide alternative implementations:

          # use My::Sub::Method instead of Kavorka::Sub::Method
          use Kavorka method => { implementation => 'My::Sub::Method' };

       Or add traits to the default implementation:

          use Kavorka method => { traits => ['My::Sub::Role::Foo'] };

       See Exporter::Tiny for more tips.

   Function Introspection API
       The coderef for any sub created by Kavorka can be passed to the "Kavorka->info" method.
       This returns a blessed object that does the Kavorka::Sub role.

          fun foo (:$x, :$y) { }

          my $info = Kavorka->info(\&foo);

          my $function_name = $info->qualified_name;
          my @named_params  = $info->signature->named_params;

          say $named_params[0]->named_names->[0];   # says 'x'

       See Kavorka::Sub, Kavorka::Signature and Kavorka::Parameter for further details.

       If you're using Moose, consider using MooseX::KavorkaInfo to expose Kavorka method
       signatures via the meta object protocol.

       Kavorka::Manual::API provides more details and examples using the introspection API.

CAVEATS

       •   As noted in Kavorka::Manual::PrototypeAndAttributes, subroutine attributes don't work
           properly for anonymous functions.

       •   This module is based on Parse::Keyword, which has a chronically broken implementation
           of closures. Kavorka uses PadWalker to attempt to work around the problem. This mostly
           seems to work, but you may experience some problems in edge cases, especially for
           anonymous functions and methods.

       •   If importing Kavorka's method modifiers into Moo/Mouse/Moose classes, pay attention to
           load order:

              use Moose;
              use Kavorka -all;   # ok

           If you do it this way, Moose's "before", "after", and "around" keywords will stomp on
           top of Kavorka's...

              use Kavorka -all;
              use Moose;          # STOMP, STOMP, STOMP!  :-(

           This can lead to delightfully hard to debug errors.

BUGS

       Please report any bugs to <http://rt.cpan.org/Dist/Display.html?Queue=Kavorka>.

SUPPORT

       IRC: support is available through in the #moops channel on irc.perl.org
       <http://www.irc.perl.org/channels.html>.

SEE ALSO

       Kavorka::Manual.

       Inspirations: <http://perlcabal.org/syn/S06.html>, Function::Parameters,
       Method::Signatures.

       <http://en.wikipedia.org/wiki/The_Conversion_(Seinfeld)>.

AUTHOR

       Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

       This software is copyright (c) 2013-2014 by Toby Inkster.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.

DISCLAIMER OF WARRANTIES

       THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
       WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
       PURPOSE.