> But support for control-flow typing of my above two examples seems like an easy addition to the TypeScript compiler - if that's what you want.
The first one is not useful and the second one is nonsensical (as there is no guarantee that there's any relation between #constructor and the type of the variable)
The first one is not useful and the second one is nonsensical (as there is no guarantee that there's any relation between #constructor and the type of the variable)