refactor DType as a Protocol

Signed-off-by: nstarman <nstarkman@protonmail.com>

Author: nstarman

src/array_api_stubs/_draft/_types.py

@@ -24,10 +24,11 @@
 
 if TYPE_CHECKING:
     from .array_object import Array
+    from .data_types import DType
 
 array = TypeVar("array", bound="Array")
 device = TypeVar("device")
-dtype = TypeVar("dtype")
+dtype = TypeVar("dtype", bound="DType")
 SupportsDLPack = TypeVar("SupportsDLPack")
 SupportsBufferProtocol = TypeVar("SupportsBufferProtocol")
 PyCapsule = TypeVar("PyCapsule")

src/array_api_stubs/_draft/data_types.py

@@ -1,22 +1,28 @@
-from ._types import dtype
+from typing import TYPE_CHECKING, Protocol
 
+if TYPE_CHECKING:
+    from ._types import dtype
 
-def __eq__(self: dtype, other: dtype, /) -> bool:
-    """
-    Computes the truth value of ``self == other`` in order to test for data type object equality.
 
-    Parameters
-    ----------
-    self: dtype
-        data type instance. May be any supported data type.
-    other: dtype
-        other data type instance. May be any supported data type.
+class DType(Protocol):
 
-    Returns
-    -------
-    out: bool
-        a boolean indicating whether the data type objects are equal.
-    """
+    def __eq__(self: dtype, other: dtype, /) -> bool:
+        """
+        Computes the truth value of ``self == other`` in order to test for data type object equality.
 
+        Parameters
+        ----------
+        self: dtype
+            data type instance. May be any supported data type.
+        other: dtype
+            other data type instance. May be any supported data type.
 
-__all__ = ["__eq__"]
+        Returns
+        -------
+        out: bool
+            a boolean indicating whether the data type objects are equal.
+        """
+        ...
+
+
+__all__ = ["DType"]