Re: [Scheme-reports] [r6rs-discuss] Date and time arithmetic library proposal for R7RS large Scheme
John Cowan 27 Nov 2010 02:00 UTC
Marc Feeley scripsit:
> Please don't count time using milliseconds. It clutters my brain to
> have to remember a different unit of time than plain seconds.
And yet the SI unit of mass is the kilogram. But I'll think about that.
> Moreover, the choice of milliseconds, rather than microseconds or
> nanoseconds is purely an artifact of the current speed of computers.
I think it's more about range vs. precision issues.
> Integers shouldn't be used for measuring time points because
> applications need different resolutions.
That's a strong point for requiring floats, but ...
> With a 64 bit float, you can represent a time interval of up to
> 3 months with a nanosecond resolution, and up to 266 years with a
> microsecond resolution. I don't see any practical reason for wanting
> more than this.
In the new all-64-bit world, 60-bit fixnums will have more range than
53-bit flonums, and they will not need to be boxed, which makes them
faster to fling around.
--
"Well, I'm back." --Sam John Cowan <cowan@ccil.org>
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