Timer requires yield to update

[IanButterworth]

I assume this is expected behavior, but I wanted to check.

This will run indefinitely, not return after 1 second.

julia> begin
           t = Timer(1)
           while isopen(t)
           end
       end

Add a yield in the loop and it returns as expected.

If that is expected, I think adding a note to the Timer docstring would be helpful.

[IanButterworth]

Perhaps isopen should yield to the timer?

[tkf]

I think isopen should be a non-synchronizing "racy" check. So, yes, I'd say it's expected.