pub fn join_context<A, B, RA, RB>(oper_a: A, oper_b: B) -> (RA, RB)Expand description
Identical to join, except that the closures have a parameter
that provides context for the way the closure has been called,
especially indicating whether they’re executing on a different
thread than where join_context was called. This will occur if
the second job is stolen by a different thread, or if
join_context was called from outside the thread pool to begin
with.