Question

When comparing a tuple with a list like …

>>> [1,2,3] == (1,2,3)
False
>>> [1,2,3].__eq__((1,2,3))
NotImplemented
>>> (1,2,3).__eq__([1,2,3])
NotImplemented

… Python does not deep-compare them as done with (1,2,3) == (1,2,3).

So what is the reason for this? Is it because the mutable list can be changed at any time (thread-safety issues) or what?

(I know where this is implemented in CPython, so please don’t answer where, but why it is implemented.)

Answer 1

You can always “cast” it

>>> tuple([1, 2]) == (1, 2)
True

Keep in mind that Python, unlike for example Javascript, is strongly typed, and some (most?) of us prefer it that way.