Re: Hypertext links in HTML (fwd)

Craig Hubley (craig@passport.ca)
Fri, 19 May 95 03:59:25 EDT

> When this discussion first started I rather liked the idea of a formal
> algebra of relations, in a separate RFC. But after thinking about it a
> bit longer I have changed my mind. In fact, I no longer see any reason
> for standardizing more than three REL values!

Me neither. Beyond those simple navigational values, things seem to
require weird 'anchor text conventions' to stay backwards compatible,
or create a very scary ambiguity between 'verb' and 'noun' semantics.

> We're trying to define relations between hypertext pages. Hypertext is
> the informal knowledge representation format par excellence and it
> would therefore be strange to straightjacket it into a formal
> relational algebra.

Yes.

> TOP, PARENT, CHILD

PARENT/CHILD implies hierarchy rather than a PATH as NEXT implies.

> HOME, BACK, FORWARD
> A document has no business trying to link to these. There is no
> way a document can assign a meaning to the document that the user
> (or robot) just left. For an applet this would be a different
> matter; one expects an applet to have access to most of the
> functions of the browser.

Well, yes, this is why I wanted "the functions of the browser" to be
named in some name space that could be extended to network-based applets.
But this seems a ways off.

> PS. Not even HyTime can type its links, except with a #FIXED attribute
> in the DTD. Some people are currently trying to get #FIXED changed to
> #REQUIRED, though.

I consider this absurd. HyTime is barely implemented, and this will just
make it harder for developers to understand and implement. They might
well kill it by forcing developers to choke down a standard type library
and implement it before they can be considered 'compliant'. In general,
'typing' is not a good idea. There have always been 'looser' and 'tighter'
data/object types in languages defined for different purposes. There
will always be need for 'strongly typed' and 'untyped' languages. This
problem, and this dichotomy, will never go away. The Internet so far has
shown a rather persistent resistance to fixed-types except for domain names,
and even this seems to be causing problems as it requires a central
authority. I suggest we leave things 'untyped' by default and let
practice in different application domains, over time, suggest any
tightening.

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