Toby Inkster > MooseX-InlineTypes-0.002 > MooseX::InlineTypes

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NAME ^

MooseX::InlineTypes - declare type constraints and coercions inline with coderefs

SYNOPSIS ^

   use v5.14;
   
   package Document {
      use Moose;
      use MooseX::InlineTypes;
      has heading => (
         traits  => [ InlineTypes ],
         is      => "ro",
         isa     => sub { !ref($_) and length($_) < 64 },
         coerce  => sub { sprintf("%s...", substr($_, 0, 60)) },
      );
   }

DESCRIPTION ^

This module provides an attribute trait that allows you to declare Moose type constraints and coercions inline using coderefs, a bit like Moo, but not quite.

isa => CODEREF

This is a coderef which returns true if the value passes the type constraint and false otherwise.

coerce => CODEREF

This is a coderef which takes the uncoerced value and returns the coerced value.

coerce => ARRAYREF

This allows you to specify several different coercions from different types:

   isa    => "ArrayRef",
   coerce => [
      Str     => sub { split /\s+/, $_ },
      HashRef => sub { sort values %$_ },
      CodeRef => sub { my @r = $_->(); \@r },
   ],

The order of coercions is significant. For example, given the following the Int coercion is never attempted, because Any is tried first!

   coerce => [
      Any     => sub { ... },
      Int     => sub { ... },
   ],

Note that coerce => CODEREF is really just a shorthand for coerce => [ Item => CODEREF ].

Attributes declared with the MooseX::InlineTypes trait do still support the "normal" Moose isa and coerce options, though it should be noted that isa=>CODE, coerce=>1 makes no sense and Moose will give you a massive warning!

EXPORT ^

InlineTypes

This is an exported constant so that you can write:

   traits  => [ InlineTypes ],

Instead of the more long-winded:

   traits  => [ "MooseX::InlineTypes::Trait::Attribute" ],
-global

If you do this:

   use MooseX::InlineTypes -global;

Then the InlineTypes trait will be applied automatically to all your attributes. (Actually only to those attributes declared using has. Attributes added via Moose meta calls will be unaffected.)

Don't worry; it's not really global. It's just for the caller.

BUGS ^

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

SEE ALSO ^

Moose, Moo.

Usage with MooseX::Types

Here's the example from the SYNPOSIS rewritten using MooseX::Types:

   use v5.14;
   
   package Document {
      use Moose;
      use MooseX::InlineTypes -global;
      use MooseX::Types qw( Str is_Str );
      has heading => (
         is      => "ro",
         isa     => sub { is_Str($_) and length($_) < 64 },
         coerce  => [
            Str, sub { sprintf("%s...", substr($_, 0, 60)) },
         ]
      );
   }

Note that MooseX::Types exports is_X functions for each type which can be useful inside the isa coderefs.

With coercion arrayrefs, beware the magic quoting power of the fat comma!

HISTORY ^

This was originally a patch for MooseX::AttributeShortcuts until Matt S Trout (cpan:MSTROUT) convinced me to rewrite it independently of that.

AUTHOR ^

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE ^

This software is copyright (c) 2012-2013 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.

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