NAME

Data::Iterator::SlidingWindow - Iteration data with Sliding Window Algorithm

SYNOPSIS

            

              
              
use Data::Iterator::SlidingWindow;
my $ i = 0;
my $iter = iterator 3 => sub{
    #generate/fetch next one.
    return if $i > 6;
    return $i++;
};
while(defined(my $cur = $iter->next())){
    # $cur is [1, 2, 3], [2, 3, 4], [3, 4, 5], [4, 5, 6]
}
            
          

And you can use <> operator.

            

              
              
while(<$iter>){
    my $cur = $_;
    ....
}
            
          

DESCRIPTION

This module is iterate elements of Sliding Window.

METHODS

iterator($window_size, $data_source)

Iterator constructor. The arguments are:

$window_size

Windows size.

$data_source

Data source of iterator.

CODE reference:

            

              
              
iterator 3 => sub{
    CODE
};
            
          

CODE returns a value on each call, and if it is exhausted, returns undef. If you want yield undefined value as a meaning value.You can use 'NULL object pattern'.

            

              
              
iterator 3 => sub{
   my $value = generate_next_value();
   return unless is_valid_value($value); # exhausted!
   return { value => $value };
};
            
          

ARRAY reference:

            

              
              
iterator 3 => \@array;
            
          

next()

Get next window.

AUTHOR

Hideaki Ohno <hide.o.j55{at}gmail.com>

SEE ALSO

LICENSE

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