function and iterable are positional only

Author: maxfischer2781

asyncstdlib/functools.py

@@ -281,6 +281,7 @@ def decorator(
 async def reduce(
     function: Union[Callable[[T, T], T], Callable[[T, T], Awaitable[T]]],
     iterable: AnyIterable[T],
+    /,
     initial: T = __REDUCE_SENTINEL,  # type: ignore
 ) -> T:
     """

asyncstdlib/functools.pyi

@@ -34,15 +34,27 @@ def cached_property(
 ) -> Callable[[Callable[[T], Awaitable[R]]], CachedProperty[T, R]]: ...
 @overload
 async def reduce(
-    function: Callable[[T1, T2], Awaitable[T1]], iterable: AnyIterable[T2], initial: T1
+    function: Callable[[T1, T2], Awaitable[T1]],
+    iterable: AnyIterable[T2],
+    /,
+    initial: T1,
 ) -> T1: ...
 @overload
 async def reduce(
-    function: Callable[[T, T], Awaitable[T]], iterable: AnyIterable[T]
+    function: Callable[[T, T], Awaitable[T]],
+    iterable: AnyIterable[T],
+    /,
 ) -> T: ...
 @overload
 async def reduce(
-    function: Callable[[T1, T2], T1], iterable: AnyIterable[T2], initial: T1
+    function: Callable[[T1, T2], T1],
+    iterable: AnyIterable[T2],
+    /,
+    initial: T1,
 ) -> T1: ...
 @overload
-async def reduce(function: Callable[[T, T], T], iterable: AnyIterable[T]) -> T: ...
+async def reduce(
+    function: Callable[[T, T], T],
+    iterable: AnyIterable[T],
+    /,
+) -> T: ...