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=pod
=encoding utf-8
=head1 NAME
Type::Tiny::Manual - an overview of Type::Tiny
=head1 SYNOPSIS
L<Type::Tiny> is a small L<Perl|http://www.perl.org/> class for writing
type constraints, inspired by L<Moose>'s type constraint API and
L<MooseX::Types>. It has only one non-core dependency (and even that is
simply a module that was previously distributed as part of Type::Tiny
but has since been spun off), and can be used with L<Moose>, L<Mouse>,
or L<Moo> (or none of the above).
Type::Tiny is used by over 1000 Perl distributions on the CPAN (Comprehensive
Perl Archive Network) and can be considered a stable and mature framework for
efficiently and reliably enforcing data types.
Type::Tiny is bundled with L<Type::Library> a framework for organizing type
constraints into collections. Also bundled is L<Types::Standard>, a
Moose-inspired library of useful type constraints. L<Type::Params> is also
provided, to allow very fast checking and coercion of function and method
parameters.
The following example gives you an idea of some of the features of these
modules. If you don't understand it all, that's fine; that's what the rest
of the manual is for. Although the example uses Moo, the C<use Moo> could
be changed to C<use Moose> or C<use Mouse> and it would still work.
use v5.36;
package Horse {
use Moo;
use Types::Standard qw( Str Int Enum ArrayRef InstanceOf );
use Type::Params qw( signature_for );
use namespace::autoclean;
has name => (
is => 'ro',
isa => Str,
required => 1,
);
has gender => (
is => 'ro',
isa => Enum[qw( f m )],
);
has age => (
is => 'rw',
isa => Int->where( '$_ >= 0' ),
);
has children => (
is => 'ro',
isa => ArrayRef[ InstanceOf['Horse'] ],
default => sub { return [] },
);
signature_for add_child => (
method => Object,
positional => [ InstanceOf['Horse'] ],
);
sub add_child ( $self, $child ) {
push $self->children->@*, $child;
return $self;
}
}
package main;
my $boldruler = Horse->new(
name => "Bold Ruler",
gender => 'm',
age => 16,
);
my $secretariat = Horse->new(
name => "Secretariat",
gender => 'm',
age => 0,
);
$boldruler->add_child( $secretariat );
use Types::Standard qw( is_Object assert_Object );
# is_Object will return a boolean
#
if ( is_Object $boldruler ) {
say $boldruler->name;
}
# assert_Object will return $secretariat or die
#
say assert_Object( $secretariat )->name;
=head1 MANUAL
Even if you are using Type::Tiny with other object-oriented programming
toolkits (such as Moose or Mouse), you should start with the Moo sections
of the manual. Most of the information is directly transferrable and the
Moose and Mouse sections of the manual list the minor differences between
using Type::Tiny with Moo and with them.
In general, this manual assumes you use Perl 5.36 or above and may use
examples that do not work on older versions of Perl. Type::Tiny does work
on earlier versions of Perl, but not all the examples and features in
the manual will run without adjustment. (For instance, you may need to
replace C<state> variables with lexical variables, avoid the
C<< package NAME { BLOCK } >> syntax, unpack C<< @_ >> instead of
using subroutine signatures, etc.)
=over
=item * L<Type::Tiny::Manual::Installation>
How to install Type::Tiny. If Type::Tiny is already installed, you can
skip this.
=item * L<Type::Tiny::Manual::UsingWithMoo>
Basic use of Type::Tiny with Moo, including attribute type constraints,
parameterized type constraints, coercions, and method parameter checking.
=item * L<Type::Tiny::Manual::UsingWithMoo2>
Advanced use of Type::Tiny with Moo, including unions and intersections,
C<stringifies_to>, C<numifies_to>, C<with_attribute_values>, and C<where>.
=item * L<Type::Tiny::Manual::UsingWithMoo3>
There's more than one way to do it! Alternative ways of using Type::Tiny,
including type registries, exported functions, and C<dwim_type>.
=item * L<Type::Tiny::Manual::Libraries>
Defining your own type libraries, including extending existing libraries,
defining new types, adding coercions, defining parameterizable types,
and the declarative style.
=item * L<Type::Tiny::Manual::UsingWithMoose>
How to use Type::Tiny with Moose, including the advantages of Type::Tiny
over built-in type constraints, and Moose-specific features.
=item * L<Type::Tiny::Manual::UsingWithMouse>
How to use Type::Tiny with Mouse, including the advantages of Type::Tiny
over built-in type constraints, and Mouse-specific features.
=item * L<Type::Tiny::Manual::UsingWithMite>
How to use Type::Tiny with Mite, including how to write an entire Perl
project using clean Moose-like code and no non-core dependencies.
(Not even dependencies on Mite or Type::Tiny!)
=item * L<Type::Tiny::Manual::UsingWithClassTiny>
Including how to Type::Tiny in your object's C<BUILD> method, and
third-party shims between Type::Tiny and Class::Tiny.
=item * L<Type::Tiny::Manual::UsingWithOther>
Using Type::Tiny with Class::InsideOut, Params::Check, and Object::Accessor.
=item * L<Type::Tiny::Manual::UsingWithTestMore>
Type::Tiny for test suites.
=item * L<Type::Tiny::Manual::Params>
Advanced information on Type::Params, and using Type::Tiny with other
signature modules like Function::Parameters and Kavorka.
=item * L<Type::Tiny::Manual::NonOO>
Type::Tiny in non-object-oriented code.
=item * L<Type::Tiny::Manual::Optimization>
Squeeze the most out of your CPU.
=item * L<Type::Tiny::Manual::Coercions>
Advanced information on coercions.
=item * L<Type::Tiny::Manual::AllTypes>
An alphabetical list of all type constraints bundled with Type::Tiny.
=item * L<Type::Tiny::Manual::Policies>
Policies related to Type::Tiny development.
=item * L<Type::Tiny::Manual::Contributing>
Contributing to Type::Tiny development.
=back
=head1 BUGS
Please report any bugs to
=head1 SEE ALSO
L<The Type::Tiny homepage|https://typetiny.toby.ink/>.
=head1 AUTHOR
Toby Inkster E<lt>tobyink@cpan.orgE<gt>.
=head1 COPYRIGHT AND LICENCE
This software is copyright (c) 2013-2014, 2017-2025 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.
=head1 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.
=cut