9.7.2 Timed Entry Calls
issues an entry call that is cancelled if the call (or a requeue-with-abort
of the call) is not selected before the expiration time is reached. A
procedure call may appear rather than an entry call for cases where the
procedure can might
be implemented by an entry.
Reason: This would be a confusing way
to call a procedure, so we only allow it when it is possible that the
procedure is actually an entry. We could have allowed formal subprograms
here, but we didn't because we'd have to allow all formal subprograms,
and it would increase the difficulty of generic code sharing.
We say “statically denotes” because
an access-to-subprogram cannot be primitive, and we don't have anything
like access-to-entry. So only names of entries or procedures are possible.
Example of a timed
-- controller too busy, try something else
Wording Changes from Ada 83
This subclause comes before the one for Conditional Entry Calls, so we
can define conditional entry calls in terms of timed entry calls.
Incompatibilities With Ada 95
A procedure call can be used as the entry_call_alternative
in a timed or conditional entry call, if the procedure might actually
be an entry. Since the fact that something is an entry could be used
in resolving these calls in Ada 95, it is possible for timed or conditional
entry calls that resolved in Ada 95 to be ambiguous in Ada 2005. That
could happen if both an entry and procedure with the same name and profile
exist, which should be rare.
Ada 2005 and 2012 Editions sponsored in part by Ada-Europe