* The value of an element's _parent attribute must either be undef or
otherwise false, or must be an element.

* The value of an element's _content attribute must either be undef or
otherwise false, or a reference to an (unblessed) array.  The array
may be empty; but if it has items, they must ALL be either mere
strings (text segments), or elements.

* The value of an element's _tag attribute should, at least, be a 
string of printable characters.

Moreover, bear these rules in mind:

* Do not break encapsulation on objects.  That is, access their
contents only thru $obj->attr or more specific methods.

* You should think twice before completely overriding any of the
methods that HTML::Element provides.  (Overriding with a method that
calls the superclass method is not so bad, though.)

=head1 SEE ALSO

L<HTML::Tree>; L<HTML::TreeBuilder>; L<HTML::AsSubs>; L<HTML::Tagset>; 
and, for the morbidly curious, L<HTML::Element::traverse>.

=head1 COPYRIGHT

Copyright 1995-1998 Gisle Aas, 1999-2004 Sean M. Burke, 2005 Andy Lester,
2006 Pete Krawczyk.

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

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.

=head1 AUTHOR

Currently maintained by Pete Krawczyk C<< <petek@cpan.org> >>

Original authors: Gisle Aas, Sean Burke and Andy Lester.

Thanks to Mark-Jason Dominus for a POD suggestion.

=cut

1;