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NAME

Zydeco::Lite - Zydeco without any magic

SYNOPSIS

  use strict;
  use warnings;
  use Zydeco::Lite;
  
  app "Local::MyApp" => sub {
    
    role "Greeting" => sub {
      
      method "greeting" => sub {
        return "Hello";
      };
    };
    
    role generator "Location" => [ "Str" ] => sub {
      my ( $gen, $arg ) = @_;
      
      method "location" => sub {
        return $arg;
      };
    };
    
    class "Hello::World" => sub {
      with "Greeting";
      with "Location" => [ "world" ];
      
      method "do_it" => [] => sub {
        my $self = shift;
        print $self->greeting, " ", $self->location, "\n";
      };
    };
  };
  
  my $obj = "Local::MyApp""->new_hello_world;
  $obj->do_it();

DESCRIPTION

Zydeco::Lite is a Zydeco-like module, but without using any parsing tricks. Zydeco requires Perl 5.14 or above, but Zydeco::Lite will run on any version of Perl since 5.8.8.

It's intended to be a happy medium between Zydeco and MooX::Press.

Syntax Examples

Apps

Apps:

  app "MyApp" => sub {
    # definition
  };

Anonymous apps:

  my $app = app sub {
    # definition
  };

Classes, Roles, Interfaces, and Abstract Classes

Classes:

  class "MyClass" => sub {
    # definition
  };

Anonymous classes:

  my $class = class sub {
    # definition
  };
  
  my $obj = $class->new();

Class generators:

  class generator "MyGen" => sub {
    my ( $gen, @args ) = ( shift, @_ );
    # definition
  };
  
  my $class = $app->generate_mygen( @args );
  my $obj   = $class->new();

  class generator "MyGen" => [ @signature ] => sub {
    my ( $gen, @args ) = ( shift, @_ );
    # definition
  };

Anonymous class generators:

  my $gen = class generator sub {
    my ( $gen, @args ) = ( shift, @_ );
    # definition
  };
  
  my $class = $gen->generate_package( @args );
  my $obj   = $class->new();

Roles, interfaces, and abstract classes work the same as classes, but use keywords role, interface, and abstract_class.

Inheritance:

  class "Base" => sub { };
  
  class "Derived" => sub {
    extends "Base";
  };

Inheritance using nested classes:

  class "Base" => sub {
    ...;
    
    class "Derived" => sub {
      ...;
    };
  };

Inheriting from a generated class:

  class generator "Base" => sub {
    my ( $gen, @args ) = ( shift, @_ );
    ...;
  };
  
  class "Derived" => sub {
    extends "Base" => [ @args ];
  };

Composition:

  role "Named" => sub {
    requires "name";
  };
  
  class "Thing" => sub {
    with "Named";
    has "name" => ();
  };

Composing an anonymous role:

  class "Thing" => sub {
    with role sub {
      requires "name";
    };
    
    has "name" => ();
  };

Composing a generated role:

  role generator "Thingy" => sub {
    my ( $gen, @args ) = ( shift, @_ );
    ...;
  };
  
  class "Derived" => sub {
    with "Thingy" => [ @args ];
  };

Package Settings

Class version:

  class "Foo" => sub {
    version "1.000";
  };

  class "Foo" => ( version => "1.0" )
              => sub {
    ...;
  };

Class authority:

  class "Foo" => sub {
    authority "cpan:TOBYINK";
  };

  class "Foo" => ( version => "1.0", authority => "cpan:TOBYINK" )
              => sub {
    ...;
  };

Using non-Moo toolkits:

  class "Foo" => sub {
    toolkit "Mouse";
  };

  class "Bat" => sub {
    toolkit "Moose" => ( "StrictConstructor" );
  };

The version, authority, and toolkit keywords can be used within app, class, role, interface, or abstract_class definitions.

Attributes

Attributes:

  has "myattr" => ( ... );
  
  has [ "myattr1", "myattr2" ] => ( ... );

Private attributes:

  has "myattr" => ( is => "private", ..., accessor => \(my $accessor) );

Methods

Methods:

  method "mymeth" => sub {
    my ( $self, @args ) = ( shift, @_ );
    ...;
  };

Methods with positional signatures:

  method "mymeth" => [ 'Num', 'Str' ]
                  => sub
  {
    my ( $self, $age, $name ) = ( shift, @_ );
    ...;
  };

Methods with named signatures:

  method "mymeth" => [ age => 'Num', name => 'Str' ]
                  => ( named => 1 )
                  => sub
  {
    my ( $self, $args ) = ( shift, @_ );
    ...;
  };

Required methods in roles:

  requires "method1", "method2";
  requires "method3";

Method modifiers:

  before "somemethod" => sub {
    my ( $self, @args ) = ( shift, @_ );
    ...;
  };

  after [ "method1", "method2"] => sub {
    my ( $self, @args ) = ( shift, @_ );
    ...;
  };

  around "another" => sub {
    my ( $next, $self, @args ) = ( shift, shift, @_ );
    ...;
    $self->$next( @_ );
    ...;
  };

Constants:

  constant "ANSWER_TO_LIFE" => 42;

Overloading:

  method "to_string" => sub {
    my $self = shift;
    ...;
  };
  
  overload(
    q[""]    => "to_string",
    fallback => 1,
  );

Factory methods:

  factory "new_foo" => \"new";

  factory "new_foo" => sub {
    my ( $factory, $class, @args ) = ( shift, shift, @_ );
    return $class->new( @args );
  };

Factory methods may include signatures like methods.

Indicate you want a class to have no factories:

  factory();

The keywords multi_method and multi_factory exist for multimethods.

Types

Setting the type name for a class or role:

  class "Foo::Bar" => sub {
    type_name "Foobar";
     ...;
  };

Coercion:

  class "Foo::Bar" => sub {
    method "from_arrayref" => sub {
      my ( $class, $aref ) = ( shift, @_ );
      ...;
    };
    coerce "ArrayRef" => "from_arrayref";
  };

  class "Foo::Bar" => sub {
    coerce "ArrayRef" => "from_arrayref" => sub {
      my ( $class, $aref ) = @_;
      ...;
    };
  };

Hooks

Hooks for classes:

  begin {
    my ( $class ) = ( shift );
    # Code that runs early during class definition
  };

  end {
    my ( $class ) = ( shift );
    # Code that runs late during class definition
  };

Hooks for roles:

  begin {
    my ( $role ) = ( shift );
    # Code that runs early during role definition
  };

  end {
    my ( $role ) = ( shift );
    # Code that runs late during role definition
  };

  before_apply {
    my ( $role, $target ) = ( shift, shift );
    # Code that runs before a role is applied to a package
  };

  after_apply {
    my ( $role, $target ) = ( shift, shift );
    # Code that runs after a role is applied to a package
  };

Utilities

Booleans:

  my $truth = true;
  my $truth = false;

Exceptions:

  confess( 'Something bad happened' );
  confess( 'Exceeded maximum (%d)', $max );

Formal Syntax

 app(
   Optional[Str]      $name,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 class(
   Optional[Str]      $name,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 class generator(
   Optional[Str]      $name,
   Optional[ArrayRef] $signature,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 role(
   Optional[Str]      $name,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 role generator(
   Optional[Str]      $name,
   Optional[ArrayRef] $signature,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 interface(
   Optional[Str]      $name,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 interface generator(
   Optional[Str]      $name,
   Optional[ArrayRef] $signature,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 abstract_class(
   Optional[Str]      $name,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 abstract_class generator(
   Optional[Str]      $name,
   Optional[ArrayRef] $signature,
   Hash               %args,
   Optional[CodeRef]  $definition,
 );
 
 extends(
   List[Str|ArrayRef] @parents,
 );
 
 with(
   List[Str|ArrayRef] @parents,
 );
 
 method(
   Optional[Str]      $name,
   Optional[ArrayRef] $signature,
   Hash               %args,
   CodeRef            $definition,
 );
 
 factory(
   Str|ArrayRef       $names,
   Optional[ArrayRef] $signature,
   Hash               %args,
   CodeRef|ScalarRef  $definition_or_via,
 );
 
 constant(
   Str                $name,
   Any                $value,
 );
 
 multi_method(
   Str                $name,
   ArrayRef           $signature,
   Hash               %args,
   CodeRef            $definition,
 );
 
 multi_factory(
   Str                $name,
   ArrayRef           $signature,
   Hash               %args,
   CodeRef            $definition,
 );
 
 before(
   Str|ArrayRef       $names,
   Optional[ArrayRef] $signature,
   Hash               %args,
   CodeRef            $definition,
 );
 
 after(
   Str|ArrayRef       $names,
   Optional[ArrayRef] $signature,
   Hash               %args,
   CodeRef            $definition,
 );
 
 around(
   Str|ArrayRef       $names,
   Optional[ArrayRef] $signature,
   Hash               %args,
   CodeRef            $definition,
 );
 
 has(
   Str|ArrayRef       $names,
   Hash               %spec,
 );
 
 requires(
   List[Str]          @names,
 );
 
 confess(
   Str                $template,
   List               @args,
 );
 
 toolkit(
   Str                $toolkit,
   Optional[List]     @imports,
 );
 
 # TODO: coerce
 
 overload(
   Hash               %args,
 );
 
 version(
   Str                $version,
 );
 
 authority(
   Str                $authority,
 );
 
 type_name(
   Str                $name,
 );
 
 begin {
   ( $package ) = @_;
   ...;
 };
 
 end {
   ( $package ) = @_;
   ...;
 };
 
 before_apply {
   ( $role, $target ) = @_;
   ...;
 };
 
 after_apply {
   ( $role, $target ) = @_;
   ...;
 };

BUGS

Please report any bugs to http://rt.cpan.org/Dist/Display.html?Queue=MooX-Press.

SEE ALSO

Zydeco, MooX::Press.

AUTHOR

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

This software is copyright (c) 2020 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.