NAME

       Moose::Meta::Attribute::Native::Trait::Hash - Helper trait for HashRef attributes

VERSION

       version 2.2203

SYNOPSIS

         package Stuff;
         use Moose;

         has 'options' => (
             traits    => ['Hash'],
             is        => 'ro',
             isa       => 'HashRef[Str]',
             default   => sub { {} },
             handles   => {
                 set_option     => 'set',
                 get_option     => 'get',
                 has_no_options => 'is_empty',
                 num_options    => 'count',
                 delete_option  => 'delete',
                 option_pairs   => 'kv',
             },
         );

DESCRIPTION

       This trait provides native delegation methods for hash references.

PROVIDED METHODS

   get($key, $key2, $key3...)
       Returns values from the hash.

       In list context it returns a list of values in the hash for the given keys. In scalar
       context it returns the value for the last key specified.

       This method requires at least one argument.

   set($key => $value, $key2 => $value2...)
       Sets the elements in the hash to the given values. It returns the new values set for each
       key, in the same order as the keys passed to the method.

       This method requires at least two arguments, and expects an even number of arguments.

   delete($key, $key2, $key3...)
       Removes the elements with the given keys.

       In list context it returns a list of values in the hash for the deleted keys. In scalar
       context it returns the value for the last key specified.

   keys
       Returns the list of keys in the hash.

       This method does not accept any arguments.

   exists($key)
       Returns true if the given key is present in the hash.

       This method requires a single argument.

   defined($key)
       Returns true if the value of a given key is defined.

       This method requires a single argument.

   values
       Returns the list of values in the hash.

       This method does not accept any arguments.

   kv
       Returns the key/value pairs in the hash as an array of array references.

         for my $pair ( $object->option_pairs ) {
             print "$pair->[0] = $pair->[1]\n";
         }

       This method does not accept any arguments.

   elements
       In list context, this returns the key/value pairs in the hash.

       In scalar context, this returns the count of keys plus values.  In other words, it's the
       same as keys times two.

       This method does not accept any arguments.

   clear
       Resets the hash to an empty value, like "%hash = ()".

       This method does not accept any arguments.

   count
       Returns the number of elements in the hash. Also useful to check for a nonempty hash,
       because "count" returns a true (nonzero) value if there is something in the hash:
       "has_options => 'count'".

       This method does not accept any arguments.

   is_empty
       If the hash is populated, returns false. Otherwise, returns true.

       This method does not accept any arguments.

   accessor($key)
   accessor($key, $value)
       If passed one argument, returns the value of the specified key. If passed two arguments,
       sets the value of the specified key.

       When called as a setter, this method returns the value that was set.

   shallow_clone
       This method returns a shallow clone of the hash reference.  The return value is a
       reference to a new hash with the same keys and values.  It is shallow because any values
       that were references in the original will be the same references in the clone.

   Why no "each"?
       We have deliberately omitted a method for "each", due to its stateful interaction with the
       hash iterator. Using "keys" or "kv" is much safer.

   Moose::Meta::Attribute->meta
       This will return a Class::MOP::Class instance for this class.

       It should also be noted that Class::MOP will actually bootstrap this module by installing
       a number of attribute meta-objects into its metaclass.

BUGS

       See "BUGS" in Moose for details on reporting bugs.

AUTHORS

       •   Stevan Little <stevan@cpan.org>

       •   Dave Rolsky <autarch@urth.org>

       •   Jesse Luehrs <doy@cpan.org>

       •   Shawn M Moore <sartak@cpan.org>

       •   יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>

       •   Karen Etheridge <ether@cpan.org>

       •   Florian Ragwitz <rafl@debian.org>

       •   Hans Dieter Pearcey <hdp@cpan.org>

       •   Chris Prather <chris@prather.org>

       •   Matt S Trout <mstrout@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2006 by Infinity Interactive, Inc.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.

perl v5.36.0                                2023-Moose::Meta::Attribute::Native::Trait::Hash(3pm)