✨ HasSize

Signed-off-by: Nathaniel Starkman <nstarman@users.noreply.github.com>

Author: nstarman

src/array_api_typing/__init__.py

@@ -8,6 +8,7 @@
     "HasMatrixTranspose",
     "HasNDim",
     "HasShape",
+    "HasSize",
     "__version__",
     "__version_tuple__",
 )
@@ -20,5 +21,6 @@
     HasMatrixTranspose,
     HasNDim,
     HasShape,
+    HasSize,
 )
 from ._version import version as __version__, version_tuple as __version_tuple__

src/array_api_typing/_array.py

@@ -6,6 +6,7 @@
     "HasMatrixTranspose",
     "HasNDim",
     "HasShape",
+    "HasSize",
 )
 
 from types import ModuleType
@@ -137,6 +138,25 @@ def shape(self) -> tuple[int | None, ...]:
         ...
 
 
+class HasSize(Protocol):
+    """Protocol for array classes that have a size attribute."""
+
+    @property
+    def size(self) -> int | None:
+        """Number of elements in an array.
+
+        Returns:
+            int | None: number of elements in an array. The returned value must
+                be `None` if and only if one or more array dimensions are
+                unknown.
+
+        Notes:
+            This must equal the product of the array's dimensions.
+
+        """
+        ...
+
+
 class Array(
     # ------ Attributes -------
     HasDType[DTypeT_co],

tests/integration/test_numpy1p0.pyi

@@ -67,6 +67,13 @@ _: xpt.HasShape = nparr
 _: xpt.HasShape = nparr_i32
 _: xpt.HasShape = nparr_f32
 
+# =========================================================
+# `xpt.HasShape`
+
+_: xpt.HasShape = nparr
+_: xpt.HasShape = nparr_i32
+_: xpt.HasShape = nparr_f32
+
 # =========================================================
 # `xpt.Array`
 

tests/integration/test_numpy2p0.pyi

@@ -77,6 +77,14 @@ _: xpt.HasShape = nparr_i32
 _: xpt.HasShape = nparr_f32
 _: xpt.HasShape = nparr_b
 
+# =========================================================
+# `xpt.HasSize`
+
+_: xpt.HasSize = nparr
+_: xpt.HasSize = nparr_i32
+_: xpt.HasSize = nparr_f32
+_: xpt.HasSize = nparr_b
+
 # =========================================================
 # `xpt.Array`