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Comment by omaranto | Hacker News Reader

    class Color(Enum):
        red, green, blue, *_ = range(2**128)
        
        red_alias = red

Does that create a list of size 2^128-3 = 340282366920938463463374607431768211453 and assign it to Color._?

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Ha! Too much Go for me. It does actually, my bad, I expected the variable to be ignored (and the range creation isn't a big deal usually as it's just a generator).

Using range would create the whole list. xrange is the one that acts like a generator :)

This Enum is slated to be introduced in Python 3.4, where range is (not acts like) a generator.

Ah. I stand corrected :)

But even with a generator, as you would get from range in Python 3, the assignment

    a, *b = range(10)

makes b into a list. (And I think the star syntax in assignments is only Python 3, as far as I remember Python 2 only has star in argument lists of functions.)

You're right, python2 doesn't have the extended unpacking (star) syntax. Furthermore, this:

    >>> a, *b = range(2**128)
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
    OverflowError: Python int too large to convert to C ssize_t

Ha.

Yes it does and that is because it actually assigns all of the rest to a variable named '_'. The use of the underscore as a throwaway variable is just a convention and the interpreter is not aware that the result should be ignored.

Looks like it.

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