On Sat, Jan 16, 2021 at 8:39 PM David Foster
On 1/12/21 1:00 PM, Matthew Rahtz via Typing-sig wrote:
Guido had a really interesting suggestion in the last tensor typing meeting: what if, instead of creating a new constructor `TypeVarTuple`, we just did `TypeVar(bound=Tuple)`?
If I understand correctly the assertion is that: TypeVarTuple is effectively the same as: TypeVar(bound=Tuple[Type, ...]) which is a bit more specific than: TypeVar(bound=Tuple) (which is the phrasing you used).
I don't think that's correct though. The bound is not a tuple of types -- since that would imply that the values described by the typevar would themselves be types. Even without generics, we can write things like ``` A = Tuple[int, int] B = Tuple[str, str, str] ``` If we generalize this to tuples of any length and any type we get `Tuple[object, ...]`, or perhaps `Tuple[Any, ...]`, but definitely not `Tuple[Type, ...]`. Usually `Type` is only needed when we are manipulating class objects. -- --Guido van Rossum (python.org/~guido) *Pronouns: he/him **(why is my pronoun here?)* http://feministing.com/2015/02/03/how-using-they-as-a-singular-pronoun-can-c...