On Tue, Aug 14, 2018 at 10:25 AM, David Mertz <mertz@gnosis.cx> wrote:
Great work! There are a few typos, I'll try to get to a PR on those.

I wonder if it's worth noting that None is a singleton, while 42 is just a value. I.e. there might be several distinct objects that happen to be the int 42, but not so with None.

very much worth nothing -- and I think re-wording that example. The fact that you can't assign to None is orthogonal to the fact that it's immutable.

in fact, [42] is a llteral for a list with one element, the integer with the value of 42 in it. It is very much a mutable. and yet:

In [7]: [42] = 34
  File "<ipython-input-7-b919f2b4d30d>", line 1
    [42] = 34
SyntaxError: can't assign to literal 


works -- at least it does not result in an error -- even though it's useless.

And the reason this matters is that name binding (and rebinding) is very much a different operation than mutating -- we should not conflate those.



Christopher Barker, Ph.D.

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