Re: Is this use of BASE kosher?

Paul Burchard (
Wed, 2 Aug 95 19:37:26 EDT

"Daniel W. Connolly" <>
> On seeing a <base href="http://here/"> element, the
> user agent treats http://here/ as the address of that
> document; hence references to http://here/#fragment
> _are_ references to the current document.

Well, that's what the simplified summary in the HTML spec says --
but unfortunately it's wrong according to the more general model of
relative URLs presented in RFC 1808.

For good reason, RFC 1808 makes *no* requirement that a document
containing relative URLs be retrievable via *any* URL, much less its
"base URL". The "base URL", by definition, serves strictly as a
device for resolving relative URLs imbedded in the document. The
examples in the RFC amply show the need for this more flexible

It's true that the most common case in Web practice is a document
obtained via an idempotent URL, having no explicitly specified base
URL. In that case, yes, retrieval of the base URL is guaranteed to
yield the same object as that in which the relative URLs are being
resolved, and the HTML spec's "optimization" of "#name" is correct.
But otherwise not.

Paul Burchard <>
``I'm still learning how to count backwards from infinity...''