NAME

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

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:

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

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, 2017-2022 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.