MooseX::AttributeHelpers::MethodProvider::List (3pm)

   package Stuff;
   use Moose;
   use MooseX::AttributeHelpers;

   has 'options' => (
       metaclass  => 'Collection::List',
       is         => 'rw',
       isa        => 'ArrayRef[Str]',
       default    => sub { [] },
       auto_deref => 1,
       provides   => {
           elements => 'all_options',
           map      => 'map_options',
           grep     => 'filter_options',
           find     => 'find_option',
           first    => 'first_option',
           last     => 'last_option',
           get      => 'get_option',
           join     => 'join_options',
           count    => 'count_options',
           empty    => 'do_i_have_options',
           sort     => 'sorted_options',
       }
   );

   no Moose;
   1;

This is a role which provides the method generators for MooseX::AttributeHelpers::Collection::List.

meta

count

Returns the number of elements in the list. $stuff = Stuff->new; $stuff->options(["foo", "bar", "baz", "boo"]);

my $count = $stuff->count_options; print "$count\n"; # prints 4

empty

If the list is populated, returns true. Otherwise, returns false. $stuff->do_i_have_options ? print "Good boy.\n" : die "No options!\n" ;

find

This method accepts a subroutine reference as its argument. That sub will receive each element of the list in turn. If it returns true for an element, that element will be returned by the \*(C`find\*(C' method. my $found = $stuff->find_option( sub { $_[0] =~ /^b/ } ); print "$found\n"; # prints "bar"

grep

This method accepts a subroutine reference as its argument. This method returns every element for which that subroutine reference returns a true value. my @found = $stuff->filter_options( sub { $_[0] =~ /^b/ } ); print "@found\n"; # prints "bar baz boo"

map

This method accepts a subroutine reference as its argument. The subroutine will be executed for each element of the list. It is expected to return a modified version of that element. The return value of the method is a list of the modified options. my @mod_options = $stuff->map_options( sub { $_[0] . "-tag" } ); print "@mod_options\n"; # prints "foo-tag bar-tag baz-tag boo-tag"

sort

Sorts and returns the elements of the list. You can provide an optional subroutine reference to sort with (as you can with the core \*(C`sort\*(C' function). However, instead of using $a and $b, you will need to use $_[0] and $_[1] instead. # ascending ASCIIbetical my @sorted = $stuff->sort_options();

# Descending alphabetical order my @sorted_options = $stuff->sort_options( sub { lc $_[1] cmp lc $_[0] } ); print "@sorted_options\n"; # prints "foo boo baz bar"

elements

Returns all of the elements of the list my @option = $stuff->all_options; print "@options\n"; # prints "foo bar baz boo"

join

Joins every element of the list using the separator given as argument. my $joined = $stuff->join_options( ':' ); print "$joined\n"; # prints "foo:bar:baz:boo"

get

Returns an element of the list by its index. my $option = $stuff->get_option(1); print "$option\n"; # prints "bar"

first

Returns the first element of the list. my $first = $stuff->first_option; print "$first\n"; # prints "foo"

last

Returns the last element of the list. my $last = $stuff->last_option; print "$last\n"; # prints "boo"

All complex software has bugs lurking in it, and this module is no exception. If you find a bug please either email me, or add the bug to cpan-RT.

Stevan Little <[email protected]>

Copyright 2007-2009 by Infinity Interactive, Inc.

<http://www.iinteractive.com>

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