in reply to Callbacks in async code

Crossposted at StackOverflow. It is considered polite to inform about crossposting, so that people not attending both sites do not waste their efforts solving a problem already solved at the other end of the wires.
لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ