[swift-evolution] [pitch] Comparison Reform

Dave Abrahams dabrahams at apple.com
Mon Apr 24 22:50:09 CDT 2017

on Mon Apr 24 2017, Xiaodi Wu <xiaodi.wu-AT-gmail.com> wrote:

> On Mon, Apr 24, 2017 at 9:06 PM, Jonathan Hull via swift-evolution <
> swift-evolution at swift.org> wrote:
>> As I am thinking about it more, this means that for == and <
>> NaN == NaN
>> -0 == +0
>> +Inf < NaN
>> Since this would break from IEEE,
> Yeah, as Steve mentioned, it's a huge deal to break from IEEE rules. 

Allow me to put it even more strongly: I consider reinventing how
floating point works to be a massive undertaking comparable to
supplanting the Unicode standard with something better.  I have no doubt
that it could be done by somebody, somewhere, someday, but it would be
easy to do something much worse than what IEEE has done, and getting it
right would occupy so much of this group's time that we couldn't hope to
accomplish anything else, if we even had the expertise—I know I don't!
Doing anything in this area that is not firmly rooted in existing
standards and practices is not an option I'm willing to pursue.


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