indexing description: "Describes an Eiffel function" class interface EIFFEL_FUNCTION creation make feature -- return type and invocation call_function (object: ANY; arguments: ARRAY [ANY]): ANY -- call if a function require conforms: valid_arguments (arguments) ensure result_conforms: result_type. has_instance (Result) result_type: EIFFEL_TYPE invariant result_type_not_void: result_type /= void; end -- class EIFFEL_FUNCTION