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NAME

Type::Tiny::Class - type constraints based on the "isa" method

SYNOPSIS

Using via Types::Standard:

package Local::Horse {
  use Moo;
  use Types::Standard qw( Str InstanceOf );
  
  has name => (
    is       => 'ro',
    isa      => Str,
  );
  
  has owner => (
    is       => 'ro',
    isa      => InstanceOf[ 'Local::Person' ],
    default  => sub { Local::Person->new },
  );
}

Using Type::Tiny::Class's export feature:

package Local::Horse {
  use Moo;
  use Types::Standard qw( Str );
  use Type::Tiny::Class 'Local::Person';
  
  has name => (
    is       => 'ro',
    isa      => Str,
  );
  
  has owner => (
    is       => 'ro',
    isa      => LocalPerson,
    default  => sub { LocalPerson->new },
  );
}

Using Type::Tiny::Class's object-oriented interface:

package Local::Horse {
  use Moo;
  use Types::Standard qw( Str );
  use Type::Tiny::Class;
  
  my $Person = Type::Tiny::Class->new( class => 'Local::Person' );
  
  has name => (
    is       => 'ro',
    isa      => Str,
  );
  
  has owner => (
    is       => 'ro',
    isa      => $Person,
    default  => sub { $Person->new },
  );
}

Using Type::Utils's functional interface:

package Local::Horse {
  use Moo;
  use Types::Standard qw( Str );
  use Type::Utils;
  
  my $Person = class_type 'Local::Person';
  
  has name => (
    is       => 'ro',
    isa      => Str,
  );
  
  has owner => (
    is       => 'ro',
    isa      => $Person,
    default  => sub { $Person->new },
  );
}

STATUS

This module is covered by the Type-Tiny stability policy.

DESCRIPTION

Type constraints of the general form { $_->isa("Some::Class") }.

This package inherits from Type::Tiny; see that for most documentation. Major differences are listed below:

Constructor

new

When the constructor is called on an instance of Type::Tiny::Class, it passes the call through to the constructor of the class for the constraint. So for example:

my $type = Type::Tiny::Class->new(class => "Foo::Bar");
my $obj  = $type->new(hello => "World");
say ref($obj);   # prints "Foo::Bar"

This little bit of DWIM was borrowed from MooseX::Types::TypeDecorator, but Type::Tiny doesn't take the idea quite as far.

Attributes

class

The class for the constraint.

constraint

Unlike Type::Tiny, you cannot pass a constraint coderef to the constructor. Instead rely on the default.

inlined

Unlike Type::Tiny, you cannot pass an inlining coderef to the constructor. Instead rely on the default.

parent

Parent is automatically calculated, and cannot be passed to the constructor.

Methods

plus_constructors($source, $method_name)

Much like plus_coercions but adds coercions that go via a constructor. (In fact, this is implemented as a wrapper for plus_coercions.)

Example:

package MyApp::Minion;

use Moose; extends "MyApp::Person";

use Types::Standard qw( HashRef Str );
use Type::Utils qw( class_type );

my $Person = class_type({ class => "MyApp::Person" });

has boss => (
   is     => "ro",
   isa    => $Person->plus_constructors(
      HashRef,     "new",
      Str,         "_new_from_name",
   ),
   coerce => 1,
);

package main;

MyApp::Minion->new(
   ...,
   boss => "Bob",  ## via MyApp::Person->_new_from_name
);

MyApp::Minion->new(
   ...,
   boss => { name => "Bob" },  ## via MyApp::Person->new
);

Because coercing HashRef via constructor is a common desire, if you call plus_constructors with no arguments at all, this is the default.

$classtype->plus_constructors(HashRef, "new")
$classtype->plus_constructors()  ## identical to above

This is handy for Moose/Mouse/Moo-based classes.

stringifies_to($constraint)

See Type::Tiny::ConstrainedObject.

numifies_to($constraint)

See Type::Tiny::ConstrainedObject.

with_attribute_values($attr1 => $constraint1, ...)

See Type::Tiny::ConstrainedObject.

Exports

Type::Tiny::Class can be used as an exporter.

use Type::Tiny::Class 'HTTP::Tiny';

This will export the following functions into your namespace:

HTTPTiny
is_HTTPTiny( $value )
assert_HTTPTiny( $value )
to_HTTPTiny( $value )

You will also be able to use HTTPTiny->new(...) as a shortcut for HTTP::Tiny->new(...).

Multiple types can be exported at once:

use Type::Tiny::Class qw( HTTP::Tiny LWP::UserAgent );

BUGS

Please report any bugs to https://github.com/tobyink/p5-type-tiny/issues.

SEE ALSO

Type::Tiny::Manual.

Type::Tiny.

Moose::Meta::TypeConstraint::Class.

AUTHOR

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

This software is copyright (c) 2013-2014, 2017-2024 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.