It's still a Python feature even if it's not a language feature, it's well defined by PEP and any type checker wanting to implement type hinting to spec must include it.

Further type hinting allows developers who want to use a Constant / Final feature get the benefit already from type hinting, whereas developers who want to stick to the pythonic philosophy of "we're all consenting adults here" can still mess with the code but know it's not supported at all. As far as I can see it's the best of both worlds.

Could you please list in your proposal the real world benefits vs. the existing type hinting feature?

On Tue, May 25, 2021 at 11:02 AM Ethan Furman <> wrote:
On 5/25/21 5:23 AM, Chris Angelico wrote:
 > On Tue, May 25, 2021 at 9:55 PM Shreyan Avigyan wrote:

 >> The proposed syntax is as follows,
 >> constant x = 10
 >> constant y = ["List"]
 >> constant z: str = "Hi"
 > Already exists :)

Optional typing != core Python.

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