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    printf $fh "circle at B%02d.c rad 0.1 filled\n", $bucket_no;
    printf $fh "arrow from B%02d.c right boxwid/2 + $bs\n", $bucket_no;
  }
}

# this method assumes that the current 'pic' position is already 
# correct, which might not be true if one of the other methods is
# overriden.  Fix it.
sub draw_node {
  my ($self, $fh, $bucket_no, $node_index, $node) = @_;
  my ($k, $v, $h, $next) = @$node;
  my ($wd, $ht) = @{$self->draw_param('KVP')};
  print $fh "boxwid:=$wd; boxht:=$ht\n";
  printf $fh qq{N%02d%02d: box "%s" "%s" "%u(%u)"\n}, $bucket_no, $node_index, $k, $v, $h, $h&($self->size * 2  - 1);
}

sub draw_start {
  my ($self, $fh) = @_;
  print $fh ".PS\n";
}

sub draw_end {
  my ($self, $fh) = @_;
  print $fh ".PE\n";
}


=head1 NAME

FakeHash::Node - Class used internally by C<FakeHash> to represent key-value pairs

=head1 SYNOPSIS

        $key   = $node->key;
        $value = $node->value;
        $hash  = $node->hash;
        $next  = $node->next;

=head1 DESCRIPTION

C<FakeHash::Node> is used internally by C<FakeHash> for various
purposes.  For example, the C<FakeHash::iterate> function invokes a
user-supplied callback for each key-value pair, passing it a series of
C<FakeHash::Node> objects that represent the key-value pairs.

The C<key> and C<value> methods retrieve the key and value of a node.
The C<hash> method retrieves the key's hash value.  

C<$node-E<gt>next> method retrieves the node that follows C<$node> in
its bucket, or an undefined value if C<$node> is last in its bucket.

If any of these methods is passed an additional argument, it will set
the corresponding value.  It will return the old value in any case.

=cut

package FakeHash::Node;

sub new {
  my ($class, @data) = @_;
  bless \@data => $class;
}

sub _access {
  my $self = shift;
  my $index = shift;
  my $oldval = $self->[$index];
  $self->[$index] = shift if @_;
  $oldval;
}

sub key {
  my $self = shift;
  $self->_access(0, @_);
}

sub value {
  my $self = shift;
  $self->_access(1, @_);
}

sub hash {
  my $self = shift;
  $self->_access(2, @_);
}

sub next {
  my $self = shift;
  $self->_access(3, @_);
}

1;

=head1 AUTHOR

Mark-Jason Dominus (C<mjd-perl-fakehash+@plover.com>)

=head1 COPYRIGHT

C<FakeHash.pm> is a Perl module that simulates the behavior of a Perl hash
variable.  C<FakeHash::DrawHash> renders a diagram of a simulated hash.

Copyright (C) 200 Mark-Jason Dominus

This program 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 2 of the License, or (at your option)
any later version.

This program 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 this program; if not, write to the Free Software Foundation, Inc., 675
Mass Ave, Cambridge, MA 02139, USA.

=cut