version errors would propagate out of event-loop-run! and could not
be caught locally.  Having read or conversion errors interfering with
anything using the event loop in this way was not a good approach, so
from version 0.13 of this library all read or conversion exceptions
will propagate in the first instance out of this procedure so that
they may be caught locally, say by putting a catch expression around
the call to this procedure, and only out of event-loop-run! if not
caught in that way.  Exceptions r