NAME

       Type::Tiny::Enum - string enum type constraints

SYNOPSIS

       Using via Types::Standard:

         package Horse {
           use Moo;
           use Types::Standard qw( Str Enum );

           has name    => ( is => 'ro', isa => Str );
           has status  => ( is => 'ro', isa => Enum[ 'alive', 'dead' ] );

           sub neigh {
             my ( $self ) = @_;
             return if $self->status eq 'dead';
             ...;
           }
         }

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

         package Horse {
           use Moo;
           use Types::Standard qw( Str );
           use Type::Tiny::Enum Status => [ 'alive', 'dead' ];

           has name    => ( is => 'ro', isa => Str );
           has status  => ( is => 'ro', isa => Status, default => STATUS_ALIVE );

           sub neigh {
             my ( $self ) = @_;
             return if $self->status eq STATUS_DEAD;
             ...;
           }
         }

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

         package Horse {
           use Moo;
           use Types::Standard qw( Str );
           use Type::Tiny::Enum;

           my $Status = Type::Tiny::Enum->new(
             name   => 'Status',
             values => [ 'alive', 'dead' ],
           );

           has name    => ( is => 'ro', isa => Str );
           has status  => ( is => 'ro', isa => $Status, default => $Status->[0] );

           sub neigh {
             my ( $self ) = @_;
             return if $self->status eq $Status->[0];
             ...;
           }
         }

STATUS

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

DESCRIPTION

       Enum type constraints.

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

   Constructors
       The "new" constructor from Type::Tiny still works, of course. But there is also:

       "new_union( type_constraints => \@enums, %opts )"
           Creates a new enum type constraint which is the union of existing enum type
           constraints.

       "new_intersection( type_constraints => \@enums, %opts )"
           Creates a new enum type constraint which is the intersection of existing enum type
           constraints.

   Attributes
       "values"
           Arrayref of allowable value strings. Non-string values (e.g. objects with overloading)
           will be stringified in the constructor.

       "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 always Types::Standard::Str, and cannot be passed to the constructor.

       "unique_values"
           The list of "values" but sorted and with duplicates removed. This cannot be passed to
           the constructor.

       "coercion"
           If "coercion => 1" is passed to the constructor, the type will have a coercion using
           the "closest_match" method.

   Methods
       "as_regexp"
           Returns the enum as a regexp which strings can be checked against. If you're checking
           a lot of strings, then using this regexp might be faster than checking each string
           against

             my $enum  = Type::Tiny::Enum->new(...);
             my $check = $enum->compiled_check;
             my $re    = $enum->as_regexp;

             # fast
             my @valid_tokens = grep $enum->check($_), @all_tokens;

             # faster
             my @valid_tokens = grep $check->($_), @all_tokens;

             # fastest
             my @valid_tokens = grep /$re/, @all_tokens;

           You can get a case-insensitive regexp using "$enum->as_regexp('i')".

       "closest_match"
           Returns the closest match in the enum for a string.

             my $enum = Type::Tiny::Enum->new(
               values => [ qw( foo bar baz quux ) ],
             );

             say $enum->closest_match("FO");   # ==> foo

           It will try to find an exact match first, fall back to a case-insensitive match, if it
           still can't find one, will try to find a head substring match, and finally, if given
           an integer, will use that as an index.

             my $enum = Type::Tiny::Enum->new(
               values => [ qw( foo bar baz quux ) ],
             );

             say $enum->closest_match(  0 );  # ==> foo
             say $enum->closest_match(  1 );  # ==> bar
             say $enum->closest_match(  2 );  # ==> baz
             say $enum->closest_match( -1 );  # ==> quux

       "is_word_safe"
           Returns true if none of the values in the enumeration contain a non-word character.
           Word characters include letters, numbers, and underscores, but not most punctuation or
           whitespace.

   Exports
       Type::Tiny::Enum can be used as an exporter.

         use Type::Tiny::Enum Status => [ 'dead', 'alive' ];

       This will export the following functions into your namespace:

       "Status"
       "is_Status( $value )"
       "assert_Status( $value )"
       "to_Status( $value )"
       "STATUS_DEAD"
       "STATUS_ALIVE"

       Multiple enumerations can be exported at once:

         use Type::Tiny::Enum (
           Status    => [ 'dead', 'alive' ],
           TaxStatus => [ 'paid', 'pending' ],
         );

   Overloading
       •   Arrayrefification calls "values".

BUGS

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

SEE ALSO

       Type::Tiny::Manual.

       Type::Tiny.

       Moose::Meta::TypeConstraint::Enum.

AUTHOR

       Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

       This software is copyright (c) 2013-2014, 2017-2023 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.