Adds handling in ArgInfo to treat empty shape as scalar arrays (#59)

hatlib/arg_info.py

@@ -58,11 +58,18 @@ class ArgInfo:
         dtype_entry = ARG_TYPES[self.hat_declared_type][DTYPE_ENTRY]
         self.numpy_dtype = self._get_type(dtype_entry)
         self.element_num_bytes = 2 if dtype_entry == "bfloat16" else self.numpy_dtype.itemsize
-        self.element_strides = param_description.affine_map
-        self.numpy_strides = tuple([self.element_num_bytes * x for x in self.element_strides])
 
-        major_dim = self.element_strides.index(max(self.element_strides))
-        self.total_element_count = self.numpy_shape[major_dim] * self.element_strides[major_dim]
+        if self.numpy_shape:
+            self.element_strides = param_description.affine_map
+            self.numpy_strides = tuple([self.element_num_bytes * x for x in self.element_strides])
+
+            major_dim = self.element_strides.index(max(self.element_strides))
+            self.total_element_count = self.numpy_shape[major_dim] * self.element_strides[major_dim]
+            
+        else:
+            self.element_strides = self.numpy_strides = self.numpy_shape = [1]
+            self.total_element_count = 1
+
         self.total_byte_size = self.element_num_bytes * self.total_element_count