Differentiating literal and forbid (Re: Personal view)

At 12:28 AM 6/18/00 +0100, David Carlisle wrote:
>[Daniel Veillard]
>>  So that "http://www.example.org/./a" is still a valid namespace name,
>> but be clearly flagged as "bad practice".
>
>While I agree that this is probably bad practice I doubt whether
>anyone has ever done this, (unlike the case for relative URI as
>namespace names, which are not that uncommon)
>If we are going to give such advice I would go further than
>recommending that ./ and ../ segments are bad practice. I think
>everyone would agree that it is probably a bad idea (but strictly
>conforming) to willfully specify two namespace names that would
>have the same functional effect as URI, so apart from /./ you could
>warn against using two namespace names that differ just by case, or using
>two different DNS names that resolve to the same server etc etc etc,
>whether this should be in the namepsace rec itself or in some advisory
>note isn't so clear

I've oscillated a few times between 'forbid' and 'literal' myself, and now
I'm settling down (since Daniel's proposal seems reasonable) to figure out
exactly what the differences in processing are.

At first, forbid seemed exactly like 'literal', minus relative URI references.

As we've continued, it seems there are cases where this is more complicated.

I've noticed:

* handling '..' and '.'

* URI protocols that are context-sensitive, i.e. file.

* URI parts that are context sensitive, i.e. private range IP addresses

The last two may or may not matter, depending on how much of the 'URI
identifies a resource' philosophy you bring into processing, and all of
them have varying importance depending on how many warning labels and/or
prohibitions make it into the final spec.

My question right now is simple.  Are there other substantive processing
differences brought on possible - even obscure - processing of absolute URI
references that could further complicate matters?

Simon St.Laurent
XML Elements of Style / XML: A Primer, 2nd Ed.
http://www.simonstl.com - XML essays and books

Received on Saturday, 17 June 2000 19:49:41 UTC