Steven> Mutable versus immutable is irrelevant. The complexity of the
Steven> object is irrelevant. The phase of the moon is irrelevant. The
Steven> *only* relevant factor is the programmer's intention:
Which for a new user not familiar with the differing concepts of "is" and
"==" can lead to mistakes.
Steven> If you find it difficult to think of a reason for testing for
Steven> identity, you're right, there aren't many. Since it's rare to
Steven> care about identity, it should be rare to use "is". But in the
Steven> few times you do care about identity, the correct solution is to
Steven> use "is" no matter what sort of object it happens to be. It
Steven> really is that simple.
Right. Again though, when newcomers conflate the concepts they can deceive
themselves into thinking "is" is just a faster "==".
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