On Tue, Jun 20, 2017 at 6:06 AM, Kushal Das <mail@xxxxxxxxxxxx> wrote: > Type annotations or type hints are purely for > external type checking tools, they do not affect the Python interpreter > anyway. Note that this statement is incorrect. Code like this: https://docs.python.org/3/library/typing.html#user-defined-generic-types where inheritance of a class from the typing module is used affects running code. Mark Shannon gave a talk at the pycon language summit and plead for the typing module to divorce type checking from inheritance and pointed out that the implementation slows down runtime. He further pointed out that using inheritance for type information like this was not a proper fit; that sometimes the class inherited from should not have anything to do with the type information. -Toshio _______________________________________________ infrastructure mailing list -- infrastructure@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to infrastructure-leave@xxxxxxxxxxxxxxxxxxxxxxx