- From: Kohsuke KAWAGUCHI <k-kawa@bigfoot.com>
- Date: Wed, 21 Feb 2001 10:34:29 -0800
- To: "Ashok Malhotra" <petsa@us.ibm.com>
- Cc: www-xml-schema-comments@w3.org

I really appreciate your reply. > I do not understand your comments re < and <=. > Would you prefer if we had separate rules for < and = ? > This would just make the algorithm longer. I see I'm sorry for my obscure writing. Let met put it in this way. My point is, the spec should define "<" relation, rather than "<=" relation. ------------- Common sense tells us that "a<=b iff a<b or a=b". I'd like this proposition to apply to dateTime type, too. (1) ------------- I assume you agree with the above statement. The current definition of order-relation of dateTime type (where one has time zone and the other doesn't) is the following: > P <= Q if P <= (Q with time zone -14) (2) > P >= Q if P >= (Q with time zone +14) > P <> Q otherwise, that is, if (Q with time zone -14) < P < (Q with time zone +14) The aforementioned common sense implies that " P<=Q iff P<Q or P=Q". In this case, since one has time zone and the other not, P is never equal to Q. Therefore, "P<=Q iff P<Q". This yields a little bit strange definition P<Q if P<=(Q with time zone-14) (3) Thus "2001-01-01T14:00:00 > 2001-01-01T00:00Z". I doubt if this is the intention of WG. If this is the intention of WG, then the spec should define '<' in this way rather than defining '<=', because '<' is the fundamental relation and '<=' is not. The spec mentioned this in section 2.4.1.2. And you may not define '<=', because the equation (1) is enough. Note that P<Q if P<(Q with time zone-14) (4) Equations (1),(3), and (4) (a common sense, the current definition, and a natural definition for '<') are inconsistent, although every two of them is consistent. I suspect the schema WG doesn't aware that these three are inconsistent. regards, ---------------------- K.Kawaguchi E-Mail: k-kawa@bigfoot.com

Received on Wednesday, 21 February 2001 13:34:31 UTC