cpp/thread/stop token/stop possible

Checks if the object has associated stop-state, and that state either has already had a stop requested or it has associated std object(s).

A default constructed has no associated stop-state, and thus cannot be stopped; the associated stop-state for which no std object(s) exist can also not be stopped if such a request has not already been made.

Parameters
(none)

Return value
if the object has no associated stop-state, or it did not yet receive a stop request and there are no associated std object(s);  otherwise.