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, 2017-2024 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.

cpanm Type::Tiny

perl -MCPAN -e shell
install Type::Tiny