- From: Ted Hardie <hardie@oakthorn.com>
- Date: Wed, 20 Feb 2002 09:23:32 -0800 (PST)
- To: connolly@w3.org (Dan Connolly)
- Cc: hardie@oakthorn.com, simonstl@simonstl.com (Simon St.Laurent), uri@w3.org, elharo@metalab.unc.edu, mnot@mnot.net (Mark Nottingham)
Me writing: > > This seems to contradict to RFC 2396, sections 2.1 and 3. > > 3, in particular, says: > > > > The URI syntax does not require that the scheme-specific-part have > > any general structure or set of semantics which is common among all > > URI. > > > > I read that to mean that http://www.bar.org/ and http://www.BAR.org/ > > may be equivalent where file://123abcdef and file://123ABCDEF might > > not be, and that a reference to the definition of the http and file > > URI schemes would be required to determine which semantics need be > > applied. Dan writing: > But that doesn't mean that http://www.bar.org/ > and http://www.BAR.org/ are the same URI. > > > In other words, the URI spec seems to say that semantic equivalence is > > scheme specific and string comparison alone is not enough. > > string comparison is enough to tell if two URIs are the same > URI. > Dan, The XML namespace doc (http://www.w3.org/TR/REC-xml-names/) cites the same RFC I did above for URI reference. It further says: URI references which identify namespaces are considered identical when they are exactly the same character-for-character. Note that URI references which are not identical in this sense may in fact be functionally equivalent. Examples include URI references which differ only in case... "identical" in the original is rendered in bold with <b></b> tags. I asssume that your statement above is that character equivalence determines whether two items meet this test (Are they "identical"?). This seems, however, to be the wrong test for this context. Actually it would be more accurate to say it would be only the first test. After determining whether two URIs meet that test an application would still need to check whether the two URIs are semantically equivalent before processing. To give a non-scheme specific example, note that RFC2141 specifies that the leading urn of a URN declaration is case insensitive and that urn:<nid>:<nss> and URN:<nid>:<nss> are equivalent. regards, Ted Hardie
Received on Wednesday, 20 February 2002 12:23:36 UTC