Nothing about nans is 'correct'. They are a CS invention
On 3/5/2015 5:26 PM, random...@fastmail.us wrote:
It's been brought up on Stack Overflow that the "in" operator (on tuples, and by my testing on dict and list, as well as dict lookup) uses object identity as a shortcut, and returns true immediately if the object being tested *is* an element of the container. However, the contains operation does not specify whether object identity or equality is to be used. In effect, the built-in container types use a hybrid test: "a is b or a == b". My question is, is this a *correct* implementation of the operator,
The current implementation of 'in' is 'correct' in that it reflects the intentions of GvR and other core developers.
-- Terry Jan Reedy -- https://mail.python.org/mailman/listinfo/python-list
