FW: single percent

Some mail didn't get sent to public-IRI which should have been:

On 2009/09/03 7:33, Larry Masinter wrote:
> Sorry to be rehashing what I think are old topics, but the discussion of these things seems to be scattered around on a zillion mailing lists:
>
>
>   *   I'm not sure why  http://example.com/%<http://example.com/%25>  should be illegal as an IRI. I remember some discussion of this, but not the resolution. Why not update IRI to allow it, since it seems to work in most systems?

Martin:

It's illegal in URIs, too. The URI and IRI syntaxes should be as 
parallel as possible. In terms of implementations, it may be easy for 
consumers, but for producers, it's not. It's much easier to just escape 
than to go and check whether (one or) two hex digits are following 
(which would change the meaning totally).

Larry:
>   *   I'm not sure why  U+0023 NUMBER SIGN should be disallowed in the characters allowed in the<fragment>  production. Again, same question...

Martin:

I seem to remember something to the effect that some implementations 
parsed URIs from the back to chop off the fragment part.


Larry:
>   *   I don't understand how current processors handle [] square brackets.  I'm reading

Martin:
Where did you read that?

Larry:
> If w begins with either of:
>     a string matching the<scheme>  production, followed by "://"
>     the string "//"
>
> then percent-encode any left or right square brackets (U+005B, U+005D, "[" and "]") following the first occurrence of "/", "?", or "#" which follows the first occurrence of "//".
>
>
> What the heck is this about?

Martin:

I think the purpose is to %-encode '[' and ']' except for the authority 
part, where they are needed for IPV6. The encoding is done because '[' 
and ']' are not allowed elsewhere than in IP-literal.

Regards,   Martin.

-- 
#-# Martin J. Dürst, Professor, Aoyama Gakuin University
#-# http://www.sw.it.aoyama.ac.jp   mailto:duerst@it.aoyama.ac.jp

Received on Friday, 25 September 2009 17:43:29 UTC