An extflonum is like a flonum, but with 80-bit precision and
not a number in the sense of `number?': only operations such as
`extfl+' work on extflonums, and only on platforms where extflonums
can be implemented by hardware without interefering with flonums
(i.e., on platforms where SSE instructions are used for
double-precision floats).
[Patch provided by Michael Filonenko and revised by Matthew.]
The compiler tracks information about bindings that are known to
hold extflonums, but the JIT does not yet exploit this information
to unbox them (except as intermediate results).
This guarantees that patterns like (? pred pat) will
always check `pred` before matching any of `pat`.
However, `and` patterns are not required to match left-
to-right.
The synchronization result of a log receiver is now a vector of four
values, instead of three, where the last one reports the name.
Also, an optional argument to `make-logger' provides a notification
callback for each event sent to the logger.
These changes enable more control over loggers and events. Suppose
that you have processes A and B, and you want all log events of A
to be visible to B, but not vice-versa. Furthermore, you want the
log events to appear at B in the right order: if A logs an event
before B, then A's event should arrive at a log receiver's before
B's. Now that a log receiver gets the name associated with the
original event, and now that the name can be re-sent in a
`log-receiver', it's possible to give A and B separate loggers and
send all of the events from A's logger to B's logger. Furthermore,
you can use the notification callback so that when an event is logged
in B, you can make sure that all available events from from A's
logger have been transferred to B's logger.
Put the details consistently with event datatypes, instead
of trying to put them all in `sync', which better reflects
the extensibility of the set of synchronizable events.
A phantom byte string is a small object that the memory
manager treats as an arbitrary-sized object, where the
size is specified when the phantom byte string is created
or or when size is changed via `set-phantom-bytes!'.
Allowing them would require support for immutable fxvectors and
flvectors, interning, and more. Since the motivation for reader
support is to make marshaling and unmarshaling easier, allow
them only in `read' mode. Change printing to make then unquotable.
