[Bug 3222] Identity and Equality

http://www.w3.org/Bugs/Public/show_bug.cgi?id=3222


cmsmcq@w3.org changed:

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------- Comment #1 from cmsmcq@w3.org  2007-10-14 18:51 -------
The WG discussed this issue at the ftf meetings of October 2007, first
as a digression from bug 3245 and then in its own right.

The primary arguments voiced against making changes here were (1) that since we
worked hard to introduce the distinction between identity and equality in 1.1,
it would feel dumb to eliminate it in effect by making nothing particular
depend on identity and (2) that it would feel dumb to use anything other than
identity for what we call *identity* constraints.  Over the course of the 
discussion, the WG came to believe that these both amount merely to a fear of 
losing face, and that they have no technical force.  It was proposed that
we could still usefully distinguish identity from equality, for purposes of 
clarity (and as a touchstone for operations intended to be identity-preserving,
such as storage and retrieval), and that we can have a note saying simply
that the term "identity constraint" is a misnomer preserved for historical
reasons.  (After the fact, some WG members also pointed out that what identity
constraints are concerned with is the identity of the element carrying the
key, not the identity of the field values themselves.  So it's misguided to 
think there is any real contradiction in using equality for identity
constraints.)

It was also pointed out that using equality rather than identity would
reduce the impact of the incompatibilities incurred by our change from 1.0
to 1.1.  This proved persuasive.

In the end, we agreed to instruct the editors to prepare draft wording
to make all tests use equality and to tell a rational story about
identity. Rationale: soften the compatibility issues involved in our
changes since 1.0.

None were opposed, but we noted that a change to equality or identity of
strings might undercut our consensus on this.

Received on Sunday, 14 October 2007 18:51:34 UTC