Re: % in URIs

Sorry peter, I had missed this before replying on www-rdf-comments.

I agree with your analysis here, the statement that %-escaping of % is 
irrelevant is untrue.

This does not impact my reply on www-rdf-comments.

Jeremy


Peter F. Patel-Schneider wrote:

> From: Jeremy Carroll <jjc@hplb.hpl.hp.com>
> Subject: % in URIs
> Date: Tue, 02 Sep 2003 18:04:15 +0100
> 
> [...]
> 
> 
>>I am not yet convinced that this materially affects RDF since we *never* 
>>require the escaping to actually be performed, it is merely a theoretical 
>>exercise that defines a set of strings. I believe that the set of strings 
>>is the same whether or not % is itself escaped.
>>
>>Jeremy
>>
> 
> From reading RFC2396 I believe that this is not the case.  In particular,
> my understanding is that http://foo.bar/oijoi% is not a legal absolute URI
> with optional fragment identifier, nor is http://foo.bar/oijoi%xy
> 
> From RDF2396:
> 
>    Because the percent "%" character always has the reserved purpose of
>    being the escape indicator, it must be escaped as "%25" in order to be
>    used as data within a URI.  Implementers should be careful not to escape
>    or unescape the same string more than once, since unescaping an already
>    unescaped string might lead to misinterpreting a percent data character
>    as another escaped character, or vice versa in the case of escaping an
>    already escaped string.
> 
> There is lots more on escaping in RDF2396.  The RDF escaping mechanism
> ignores most the subtleties involved.  
> 
> Peter F. Patel-Schneider
> 
>

Received on Tuesday, 9 September 2003 04:08:56 UTC