[Python-Dev] A proposal has surfaced on comp.lang.python
Guido van Rossum
guido at python.org
Wed Mar 17 19:59:52 EST 2004
> I can understand why you might be disinclined, but I do see why recursive
> "is" might be cheaper. The simplest case is probably comparing two
> 2-element tuples, where the elements are arbitrary objects. == might not
> even be defined on those objects, but "is" would be.
Ah, but that would be definite incompatible change in semantics. I
would be very suprised if this printed "IS":
a = 
b = 
if (a, b) is (a, b): print "IS"
else: print "ISN'T"
--Guido van Rossum (home page: http://www.python.org/~guido/)
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