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I'm a big fan of this. I really want structural subtyping for http://github.com/google/pytype.
On Mon, Mar 20, 2017 at 5:00 AM, Ivan Levkivskyi <levkivskyi@gmail.com> wrote:
Explicitly declaring implementation-----------------------------------
To explicitly declare that a certain class implements the given protocols,
Why is this necessary? The whole point of ducktyping is that you \*don't\* have to declare what you implement.
I get that it looks convenient to have your protocol A also supply some of the methods you'd expect classes of type A to have. But completing an implementation in that way should be done explicitly (via including a utility class or using a decorator like functools.total\_ordering), not as side-effect of an (unnecessary) protocol declaration.