+ writeln!(w, "/// Checks if the given object is currently in the success state").unwrap();
+ writeln!(w, "#[no_mangle]").unwrap();
+ writeln!(w, "pub extern \"C\" fn {}_is_ok(o: &{}) -> bool {{", mangled_container, mangled_container).unwrap();
+ writeln!(w, "\to.result_ok").unwrap();
+ writeln!(w, "}}").unwrap();
+