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Type::Tiny::Manual::UsUseriContributed PType::Tiny::Manual::UsingWithMite(3pm)

NAME
       Type::Tiny::Manual::UsingWithMite - how to use Type::Tiny with Mite

MANUAL
       Mite takes an unorthodox approach to object-oriented code. When you
       first start a project with Mite (which we'll assume is called
       Your::Project), Mite will create a module called Your::Project::Mite
       for you.

       Then all your classes use code like:

          package Your::Project::Widget;

          use Your::Project::Mite -all;

          has name => (
             is => ro,
             isa => 'Str',
          );

          has id => (
             is => ro,
             isa => 'PositiveInt',
          );

          signature_for warble => (
             named => [
                foo   => 'Int',
                bar   => 'ArrayRef',
             ],
          );

          sub warble {
             my ( $self, $arg ) = @_;
             printf( "%s: %d\n", $self->name, $arg->foo );
             return;
          }

          1;

       After writing or editing each class or role, you run the command "mite
       compile" and Mite will output a collection of compiled Perl classes
       which have no non-core dependencies (on Perl 5.14+. There are a couple
       of non-core dependencies on older versions of Perl.)

       Attribute "isa" options are Type::Tiny type constraints expressed as
       strings. Mite looks them up during compilation using "dwim_type" from
       Type::Utils, and pre-loads Types::Standard, Types::Common::String, and
       Types::Common::Numeric for you.

       The "signature_for" keyword is similar to the corresponding function in
       Type::Params. Again, note that types are expressed as strings and
       looked up using "dwim_type".

       Any types which are inlineable should work. If using coercion, any
       coercions which are inlineable should work.

   Custom Types in Mite
       You can define your own type library (say, Your::Project::Types) using
       Type::Library as normal:

          package Your::Project::Types;

          use Type::Library
             -extends => [ 'Types::Standard', 'Types::Common::Numeric' ];

          __PACKAGE__->add_type(
             name    => 'Widget',
             parent  => InstanceOf['Your::Project::Widget'],
          )->coercion->add_type_coercions(
             HashRef, q{Your::Project::Widget->new($_)},
          );

          __PACKAGE__->make_immutable;

          1;

       Now if your classes load Your::Project::Types they'll suddenly have a
       dependency on Type::Library, so you don't get that nice zero-dependency
       feeling. But you can add this to your ".mite/config" file:

          types: Your::Project::Types

       Now Mite will know to load that type library at compile time, and will
       make those types available as stringy types everywhere.

   Compiled Type Libraries
       It does look really pretty to not have to quote your type constraints:

          has name => (
             is   => ro,
             isa  => Str,
          );

       One solution for that is Type::Library::Compiler.

       Say you've created the custom type library above, you can use
       Type::Library::Compiler to compile it into a module called
       Your::Project::Types::Compiled, which just uses Exporter and doesn't
       rely on Type::Library or any other part of Type::Tiny.

       Then your Widget class can use that:

          package Your::Project::Widget;

          use Your::Project::Mite -all;
          use Your::Project::Types::Compiled -types;

          has name => (
             is   => ro,
             isa  => Str,
          );

          has id => (
             is   => ro,
             isa  => PositiveInt,
          );

          signature_for warble => (
             named => [
                foo   => Int,
                bar   => ArrayRef,
             ],
          );

          sub warble {
             my ( $self, $arg ) = @_;
             printf( "%s: %d\n", $self->name, $arg->foo );
             return;
          }

          1;

       The compiled type libraries are more limited than real type libraries.
       You can't, for example, do parameterized types with them. However, they
       still offer some cool features like:

          Foo->check( $value )     # a few basic methods like this
          is_Foo( $value )         # boolean checks
          assert_Foo( $value )     # assertions which die
          Foo | Bar                # unions!

       This way you can write a project with object orientation, roles, method
       modifiers, type-checked attributes, type-checked signatures, and even
       coercion, with no non-core dependencies! (The tools like Mite and
       Type::Library::Compiler are only needed by the developer, not the end
       user.)

NEXT STEPS
       Here's your next step:

       •   Type::Tiny::Manual::UsingWithClassTiny

           Including how to Type::Tiny in your object's "BUILD" method, and
           third-party shims between Type::Tiny and Class::Tiny.

AUTHOR
       Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE
       This software is copyright (c) 2022-2023 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.

perl v5.36.0                      2023-0Type::Tiny::Manual::UsingWithMite(3pm)

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