Motion P1788/M0036.03:Flavors - YES
I vote YES on Motion 36.
The argument that we can always deal with this issue later
does not work, because it would INVALIDATE a standard that
does not allow for the possibility of multiple flavours.
This is different from the addition of DFP to IEEE 754.
None of the properties of BFP defined in 754-2008 were
invalidated; some were strengthened (should -> shall),
and some requirements were dropped (trap specifications
for wrapped exponents), but other improvements (such as
unifying NaN treatment) had to be phrased as SHOULD to
avoid invalidating the old standard.
Motion 36 does not require that multiple flavours be supported.
It only provides a framework for doing so. The fact that modal
intervals may not (in some work group member's opinions) be ready
for prime time would then NOT delay the standardization of the
flavour that has the widest support and most solid foundation (in
some opinions) in reasonable time.
Some have suggested that the Motion 3 interval flavour be required.
I don't think that it necessary. If and when, say, a modal flavour
will have been formulated in a manner that allows it to be included
in the standard, a vendor who is only interested in that flavour
would not be able to provide a conforming implementation without
doing the extra work of providing also a full second flavour.
There was also (primarily offline) a detailed discussion of the
interactions between different flavours, and the possibility that
even different types might be treated as different flavours --
sort of getting into the perfume business brought up by Dima. In
my opinion the primary utility of flavours is that it allows ONE
flavour to be available in a standard form for a program to exploit.
It would be a DIFFERENT program that takes advantage of another
flavour. The mechanism for supporting multiple flavours in one
program should be there to allow specialised interface programs to
be written in a portable and standard-conforming manner. Yes, some
programmers may be able to exploit multiple flavours (when available
in an integrated manner in some environment) for interesting effects,
but the main application of the standard will be for single-flavour
programs.
Michel.
---Sent: 2012-08-28 12:59:33 UTC