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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
    If seeing test failures on threaded Perl 5.21+, it may be a bug in
    Devel::CallParser 0.002. Try installing
    Alt::Devel::CallParser::ButWorking.

    Please report any other 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, 2017 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.