[Python-Dev] == on object tests identity in 3.x

Stephen J. Turnbull stephen at xemacs.org
Tue Jul 8 05:34:33 CEST 2014

Ethan Furman writes:

 > And what would be this 'sensible definition' [of value equality]?

I think that's the wrong question.  I suppose Andreas's point is that
when the programmer doesn't provide a definition, there is no such
thing as a "sensible definition" to default to.  I disagree, but given
that as the point of discussion, asking what the definition is, is moot.

 > 2) The 'is' operator is specialized, and should only rarely be
 >    needed.

Nitpick: Except that it's the preferred way to express identity with
singletons, AFAIK.  ("if x is None: ...", not "if x == None: ...".)

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