Robert Boone


MooseX::Iterator - Iterate over collections


Access the Iterator directly:

    use Moose;
    use MooseX::Iterator;

    my $iter = MooseX::Iterator::Array->new( collection => [ 1, 2, 3, 4, 5, 6 ] );

    my $count = 1;
    while ( $iter->has_next ) {
        print $iter->next;

Or use the meta class:

    package TestIterator;

    use Moose;
    use MooseX::Iterator;

    has collection => (
        is      => 'ro',
        isa     => 'HashRef',
        default => sub { { one => '1', two => '2', three => '3' } },

    has iter => (
        metaclass    => 'Iterable',
        iterate_over => 'collection',

    no Moose;

    package main;
    use Data::Dumper;

    my $test = TestIterator->new;

    my $iter = $test->iter;

    while ( $iter->has_next ) {
        my $next = $iter->next;
        print $next->{'key'}   . "\n";
        print $next->{'value'} . "\n";


This is an attempt to add smalltalk-like streams to Moose. It currently works with ArrayRefs and HashRefs.


The next method provides the next item in the colletion.

  For arrays it returns the element of the array
  For hashs it returns a pair as a hashref with the keys: key and value

The has_next method is a boolean method that is true if there is another item in the colletion after the current item. and falue if there isn't.


The peek method returns the next item without moving the state of the iterator forward. It returns undef if it is at the end of the collection.


Resets the cursor, so you can iterate through the elements again.

Subclassing MooseX::Iterator::Meta::Iterable

When subclassing MooseX::Iterator::Meta::Iterable for your own iterators override MooseX::Iterator::Meta::Iterable::_calculate_iterator_class_for_type to returns the name of the class that iterates over your new collection type. The class must implement the MooseX::Iterator::Role role.


Robert Boone <>

And thank you to Steven Little (steven) and Matt Trout (mst) for the help and advice they gave.


Johannes Plunien

Code Repository

 Git -


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

1 POD Error

The following errors were encountered while parsing the POD:

Around line 96:

'=item' outside of any '=over'