Re: URI vs. URI reference for system identifiers

[Bjoern Hoehrmann <derhoermi@gmx.net>]

* John Cowan wrote:
>Bjoern Hoehrmann scripsit:
>
>> As per RFC 2396, the difference between an URI and an URI reference is,
>> that the URI reference allows an additional fragment identifier attached
>> to the URI. 
>
>A URI reference may also be relative to the current base, whereas a URI
>is always absolute.  The intent here is to permit both relative and absolute
>forms, but not fragment identifiers.

I can get these two rules from RFC 2396

  * URIs may be absolute or relative (absoluteURI or relativeURI)
  * URI references may contain a fragment identifier

Using URI references and _disallowing_ the fragment identifier breaks
with these rules. The specification should just say

  "[Definition: The SystemLiteral is called the entity's system
   identifier. It is either an absolute or relative URI (as defined in
   [IETF RFC 2396], updated by [IETF RFC 2732]), meant to be
   dereferenced to obtain input for the XML processor to construct the
   entity's replacement text.]"

Otherwise it's just abuse of the term "URI reference", connected to the
production in RFC 2396

  URI-reference = [ absoluteURI | relativeURI ] [ "#" fragment ]

The WG should take it into serious consideration to clarify this in the
errata and future XML recommendations.

Anyway, thanks for your explanation.
-- 
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