NAME

Type::Tiny::ConstrainedObject - shared behavour for Type::Tiny::Class, etc

STATUS

This module is considered experiemental.

DESCRIPTION

Methods

The following methods exist for Type::Tiny::Class, Type::Tiny::Role, Type::Tiny::Duck, and any type constraints that inherit from Object or Overload in Types::Standard.

These methods will also work for Type::Tiny::Intersection if at least one of the types in the intersection provides these methods.

These methods will also work for Type::Tiny::Union if all of the types in the union provide these methods.

stringifies_to($constraint)

Generates a new child type constraint which checks the object's stringification against a constraint. For example:

   my $type  = Type::Tiny::Class->new(class => 'URI');
   my $child = $type->stringifies_to( StrMatch[qr/^http:/] );
   
   $child->assert_valid( URI->new("http://example.com/") );

In the above example, $child is a type constraint that checks objects are blessed into (or inherit from) the URI class, and when stringified (e.g. though overloading) the result matches the regular expression qr/^http:/.

$constraint may be a type constraint, something that can be coerced to a type constraint (such as a coderef returning a boolean), a string of Perl code operating on $_, or a reference to a regular expression.

So the following would work:

   my $child = $type->stringifies_to( sub { qr/^http:/ } );
   my $child = $type->stringifies_to(       qr/^http:/   );
   my $child = $type->stringifies_to(       'm/^http:/'  );
   
   my $child = $type->where('"$_" =~ /^http:/');
numifies_to($constraint)

The same as stringifies_to but checks numification.

The following might be useful:

   use Types::Standard qw(Int Overload);
   my $IntLike = Int | Overload->numifies_to(Int)
with_attribute_values($attr1 => $constraint1, ...)

This is best explained with an example:

   use Types::Standard qw(InstanceOf StrMatch);
   use Types::Common::Numeric qw(IntRange);
   
   my $person = InstanceOf['Local::Human'];
   my $woman  = $person->with_attribute_values(
      gender   => StrMatch[ qr/^F/i  ],
      age      => IntRange[ 18 => () ],
   );
   
   $woman->assert_valid($alice);

This assertion will firstly check that $alice is a Local::Human, then check that $alice->gender starts with an "F", and lastly check that $alice->age is an integer at least 18.

Again, constraints can be type constraints, coderefs, strings of Perl code, or regular expressions.

Technically the "attributes" don't need to be Moo/Moose/Mouse attributes, but any methods which can be called with no parameters and return a scalar.

BUGS

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

SEE ALSO

Type::Tiny::Manual.

Type::Tiny.

AUTHOR

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

This software is copyright (c) 2019 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.