Michael Shipper
and 1 contributors


Data::Range::Compare::Stream::Iterator::Base - Abstract class


  package MyIterator;
  use strict;
  use warnings;
  use IO::File;
  use IO::Select;
  use base qw(Data::Range::Compare::Stream::Iterator::Base);
  use Data::Range::Compare::Stream;
  sub new {
    my ($class,%args)=@_;
    my $has_next;
    my $self=$class->SUPER::new(%args);
    if(defined($args{filename})) {
      my $fh=IO::File->new($args{filename});
      if($fh) {
         my $line=$fh->getline;
      } else {
        $self->{msg}="Error could not open $args{filename} error was: $!";
    return $self;
  sub get_next {
    my ($self)=@_;
    return undef unless $self->has_next;
    my $line=$self->{next_line};
    $self->{has_next}=$self->{next_line} ?  1 : 0;
    chomp $line;
    return new Data::Range::Compare::Stream(split /\s+/,$line);


This module acts as the base class for all Data::Range::Compare::Stream::Iterator classes.

Methods to implement

  • my $iterator=new MyIterator(arguments=>here);

    The default object constructor takes a hash of arguments, and returns a blessed anonymous hash. If you want to do anything other than that you will need to overload this function!

  • while($iterator->has_next) { do something }

    The internals return $self->{has_next}. If you want to do anything other than that you will need to overload this function!

  • my $range=$iterator->get_next;

    Objects returned from this function should extend Data::Range::Compare::Stream::Result::Base

  • my $string=$iterator->to_string;

    Returns the package name of $iterator

  • $iterator->on_consolidate;

    This object needs to be called when ranges are being consolidated.

  • $iterator->delete_from_root($id);

    Deletes $id from $iterator.

  • if($iterator->is_child) { ... }

    Returns true if the object was auto generated by another object.

  • if($iterator->has_child) { ... }

    Returns true if this $iterator auto generated a new iterator object

  • my $id=$iterator->get_column_id

    Returns the column id of this $iterator.

  • $iterator->set_column_id($id);

    Sets the column id of $iterator

  • if($iterator->has_root) { ... }

    Returns true if this $iterator was auto generated by another iterator.

  • my $root=$iterator->get_root;

    Returns the root object if $iterator->has_root is true.

  • my $id=$iterator->get_root_column_id;

    Returns the column_id of the object that auto generated $iterator, returns current column_id of the object was not auto generated.

  • my $child=$iterator->get_child;

    Returns the child object if $iterator->has_child is true.

  • my $id=$iterator->get_child_column_id;

    Returns the child column_id if $iterator->has_child is true.

  • my $line=$iterator->result_to_line($range);

    Given a $result from $iterator->get_next, this interface converts the $range object into a line that can be parsed by $iterator->parse_line($line). Think of this function as a data serializer for range objects generated by an $iterator object. When overloading this function or using a call back make sure result_to_line can be parsed by parse_line.

      sub result_to_line {
        my ($self,$result)=@_;
        return $self->{result_to_line}->($result) if defined($self->{result_to_line});
        my $range=$result->get_common;
        my $line=$range->range_start_to_string.' '.$range->range_end_to_string."\n";
        return $line;
  • my $ref=$iterator->parse_line($line);

    Given a $line returns the arguments required to construct an object that extends or implements Data::Range::Compare::Stream. When overloading or passing in constructor arguments that provide a call back make sure result_to_line produces the expected line parse_line expects.

      sub parse_line {
        my ($self,$line)=@_;
        return $self->{parse_line}->($line) if defined($self->{parse_line});
        chomp $line;
        [split /\s+/,$line];




Michael Shipper

Source-Forge Project

As of version 0.001 the Project has been moved to Source-Forge.net

Data Range Compare https://sourceforge.net/projects/data-range-comp/


Copyright 2011 Michael Shipper. All rights reserved.

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