TYP: it's a bad idea to import TypeAlias from typing on python<3.10

Author: jorenham

array_api_compat/common/_fft.py

@@ -1,9 +1,9 @@
 from collections.abc import Sequence
-from typing import Literal, TypeAlias
+from typing import Literal
 
 from ._typing import Array, Device, DType, Namespace
 
-_Norm: TypeAlias = Literal["backward", "ortho", "forward"]
+_Norm = Literal["backward", "ortho", "forward"]
 
 # Note: NumPy fft functions improperly upcast float32 and complex64 to
 # complex128, which is why we require wrapping them all here.

array_api_compat/common/_helpers.py

@@ -11,16 +11,7 @@
 import math
 import sys
 import warnings
-from typing import (
-    TYPE_CHECKING,
-    Any,
-    Literal,
-    SupportsIndex,
-    TypeAlias,
-    TypeGuard,
-    cast,
-    overload,
-)
+from typing import TYPE_CHECKING, Any, Literal, SupportsIndex, TypeGuard, cast, overload
 
 from ._typing import Array, Device, HasShape, Namespace, SupportsArrayNamespace
 
@@ -34,7 +25,7 @@
     import numpy.typing as npt
     import sparse  # pyright: ignore[reportMissingTypeStubs]
     import torch
-    from typing_extensions import TypeIs, TypeVar
+    from typing_extensions import TypeAlias, TypeIs, TypeVar
 
     _SizeT = TypeVar("_SizeT", bound=int | None)
 

array_api_compat/numpy/_aliases.py

@@ -13,9 +13,9 @@
 from ._typing import Array, Device, DType
 
 if TYPE_CHECKING:
-    from typing import Any, Literal, TypeAlias
+    from typing import Any, Literal
 
-    from typing_extensions import Buffer, TypeIs
+    from typing_extensions import Buffer, TypeAlias, TypeIs
 
     _Copy: TypeAlias = py_bool | Literal[2] | np._CopyMode
 

array_api_compat/numpy/_typing.py

@@ -3,12 +3,14 @@
 __all__ = ["Array", "DType", "Device"]
 _all_ignore = ["np"]
 
-from typing import TYPE_CHECKING, Any, Literal, TypeAlias
+from typing import TYPE_CHECKING, Any, Literal
 
 import numpy as np
 
-Device: TypeAlias = Literal["cpu"]
+Device = Literal["cpu"]
 if TYPE_CHECKING:
+    from typing_extensions import TypeAlias
+
     # NumPy 1.x on Python 3.9 and 3.10 fails to parse np.dtype[]
     DType: TypeAlias = np.dtype[
         np.bool_