[Python-ideas] Should Python have user-defined constants?

[Ivan Levkivskyi]

On 21 November 2017 at 10:47, Paul Moore <p.f.moore at gmail.com> wrote:

> -1. I don't see how this would improve any programs I've written or
> seen. Tools like mypy or linters might benefit from a feature to track
> constants and ensure they don't get changed
>

It is actually likely that something like this will appear in ``typing``:

    from typing import Final, List

    x: Final = 42
    x = 1  # Fails type check

    lst: Final[List[int]] = []
    lst.append(5)  # OK
    lst = [1, 2, 3]  # Fails type check

--
Ivan
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