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                $self->skipspace;
                $ts->[ $i++ ] = $self->_term;
                $self->skipspace;
            }
            else {
                $ts->[ $i++ ] = $term->new( NULL, 0 );
            }

            if ( ']' ne $self->current ) {
                $self->parseerror("Expecting ']'");
            }

            $self->advance;
            $term->{bound}   = 1;
            $term->{deref}   = 0;
            $term->{functor} = "cons";
            $term->{arity}   = 2;
            $term->{args}    = [];
            for my $j ( reverse 1 .. $i - 2 ) {
                my $term = $term->new( "cons", 2 );
                $term->setarg( 0, $ts->[$j] );
                $term->setarg( 1, $ts->[ $j + 1 ] );
                $ts->[$j] = $term;
            }
            $term->{args}[0] = $ts->[0];
            $term->{args}[1] = $ts->[1];
        }
    }
    elsif ( '!' eq $self->current ) {
        $self->advance;
        return $term->CUT;
    }
    else {
        $self->parseerror(
            "Term should begin with a letter, a digit, or '[', not a @{[$self->current]}"
        );
    }
    return $term;
}

1;

__END__

=head1 NAME

AI::Prolog::Parser - A simple Prolog parser.

=head1 SYNOPSIS

 my $database = Parser->consult($prolog_text).

=head1 DESCRIPTION

There are no user-serviceable parts inside here.  See L<AI::Prolog|AI::Prolog>
for more information.  If you must know more, there are a few comments
sprinkled through the code.

=head1 SEE ALSO

W-Prolog:  L<http://goanna.cs.rmit.edu.au/~winikoff/wp/>

Michael BartE<225>k's online guide to programming Prolog:
L<http://kti.ms.mff.cuni.cz/~bartak/prolog/index.html>

=head1 AUTHOR

Curtis "Ovid" Poe, E<lt>moc tod oohay ta eop_divo_sitrucE<gt>

Reverse the name to email me.

This work is based on W-Prolog, L<http://goanna.cs.rmit.edu.au/~winikoff/wp/>,
by Dr. Michael Winikoff.  Many thanks to Dr. Winikoff for granting me
permission to port this.

=head1 COPYRIGHT AND LICENSE

Copyright 2005 by Curtis "Ovid" Poe

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

=cut