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# Copyright 2010, 2011, 2012, 2013, 2014 Kevin Ryde

# This file is part of Math-NumSeq.
#
# Math-NumSeq is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 3, or (at your option) any later
# version.
#
# Math-NumSeq is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# for more details.
#
# You should have received a copy of the GNU General Public License along
# with Math-NumSeq.  If not, see <http://www.gnu.org/licenses/>.

package Math::NumSeq::Base::Array;
use 5.004;
use strict;

use vars '$VERSION', '@ISA';
$VERSION = 69;

use Math::NumSeq;
@ISA = ('Math::NumSeq');

# uncomment this to run the ### lines
#use Smart::Comments;

# sub new {
#   my $class = shift;
#   my $self = $class->SUPER::new (@_);
#   my $array = $self->{'array'};
#   if ($self->{'lo'}) {
#     while (@$array && (! defined $array->[0] || $array->[0] < $self->{'lo'})) {
#       shift @$array;
#     }
#   }
#   ### shifted to: @$array
#   return $self;
# }
sub rewind {
  my ($self) = @_;
  $self->{'i'} = $self->i_start;
}
sub next {
  my ($self) = @_;
  ### ValuesArray next(): $self->{'i'} . ' of ' . scalar(@{$self->{'array'}})
  my $array = $self->{'array'};
  my $i;
  for (;;) {
    if (($i = $self->{'i'}++) > $#$array) {
      return;
    }
    if (defined (my $n = $self->{'array'}->[$i])) {
      return ($i, $n);
    }
  }
}
sub pred {
  my ($self, $n) = @_;
  return exists (($self->{'hash'} ||= do {
    my %h;
    @h{grep {defined} @{$self->{'array'}}} = ();
    ### %h
    \%h
  })->{$n});
}
sub ith {
  my ($self, $i) = @_;
  return $self->{'array'}->[$i];
}

1;
__END__