[Bug 3224] Inequality

http://www.w3.org/Bugs/Public/show_bug.cgi?id=3224





------- Comment #10 from davep@iit.edu  2007-04-20 18:24 -------
(In reply to comment #9)

> Not that they cannot be compared.  In fact, they can be compared, and the
> answers are that 23 <> 2007-04-20 is true, and 23 = 2007-04-20, 23 <
> 2007-04-20, and 23 > 2007-04-20 are all three false.  Of the derived
> comparisons, 23 != 2007-04-20 is true, and 23 <= 2007-04-20 and 23 >=
> 2007-04-20 aree false.

As I think about it, in fact "<>" is just as much a derived relation as are
"!=", "<=", and ">=".  The other three are in some sense primitive and these
four (and the negations of "<" and ">", which we do not suggest a notation for,
and do not use) are defined in terms of the first three.  Admittedly other
choices of three primitives from the nine are possible and the other six
defined therefrom; this just happens to be a common choice and the one we've
used to explain our use of all.

Received on Friday, 20 April 2007 18:25:29 UTC