✨: add HasArrayRMatmul protocol to support right matrix multiplication operator for array classes

Author: nstarman

src/array_api_typing/_array.py

@@ -434,6 +434,22 @@ def __imatmul__(self, other: Self, /) -> Self:
         ...
 
 
+class HasArrayRMatmul(Protocol):
+    """Protocol for array classes that support the right matrix multiplication operator."""  # noqa: E501
+
+    def __rmatmul__(self, other: Self, /) -> Self:
+        """Calculates the matrix product for each element of an array instance with the respective element of the array other.
+
+        Args:
+            other: multiplicand array. Must be compatible with self (see Broadcasting). Should have a numeric data type.
+
+        Returns:
+            an array containing the element-wise matrix products. The returned array must have a data type determined by Type Promotion Rules.
+
+        """  # noqa: E501
+        ...
+
+
 class HasArrayInvert(Protocol):
     """Protocol for array classes that support the inverse operator."""
 
@@ -731,6 +747,7 @@ class Array(
     HasArrayRPow,
     HasArrayMatmul,
     HasArrayIMatmul,
+    HasArrayRMatmul,
     HasArrayInvert,
     HasArrayAnd,
     HasArrayIAnd,