File Coverage

blib/lib/Array/Stream/Transactional.pm

Criterion	Covered	Total	%
statement	64	64	100.0
branch	4	8	50.0
condition	1	3	33.3
subroutine	17	17	100.0
pod	13	13	100.0
total	99	105	94.2

# $Id: Transactional.pm,v 1.6 2004/04/08 19:36:28 claes Exp $

package Array::Stream::Transactional;

use 5.00503;
use Carp qw(croak);
use strict;
use warnings;

our $VERSION = '1.02';

sub new {
  my ($class, $tokens) = @_;
  $class = ref $class || $class;
  croak "Not an ARRAY reference" unless(UNIVERSAL::isa($tokens, "ARRAY"));
  my $self = bless { data => $tokens }, $class;
  $self->reset;

  return $self;
}

sub reset {
  my $self = shift;
  $self->{pos} = 0;
  $self->{transactions} = [];
  $self->{current} = $self->{data}->[0];
  $self->{previous} = undef;
  1;
}

sub pos {
  $_[0]->{pos};
}

sub next {
  my $self = shift;
  $self->{previous} = $self->{current};
  $self->{current} = $self->{data}->[++$self->{pos}];
  return $self->{current};
}

sub rewind {
  my $self = shift;
  $self->{previous} = $self->{current};
  $self->{current} = $self->{data}->[--$self->{pos}];
  return $self->{current};
}

sub following {
  my $self = shift;
  return undef if($self->{pos} == @{$self->{data}});
  return $self->{data}->[$self->{pos} + 1];
}

sub commit {
  my $self = shift;
  push @{$self->{transactions}}, [ $self->{pos}, $self->{current}, $self->{previous} ];
  1;
}

sub rollback {
  my $self = shift;
  croak "No more commits to rollback" unless(@{$self->{transactions}});
  ($self->{pos}, $self->{current}, $self->{previous}) = @{pop @{$self->{transactions}}};
  1;
}

sub regret {
  my $self = shift;
  croak "No more commits to regret" unless(@{$self->{transactions}});
  return @{pop @{$self->{transactions}}};
}

sub current {
  my $self = shift;
  return $self->{current};
}

sub previous {
  my $self = shift;
  return $self->{previous};
}

sub length {
  my $self = shift;
  return scalar @{$self->{data}};
}

sub has_more {
  my $self = shift;
  return $self->{pos} < @{$self->{data}};
}

1;

__END__