On 12/11/10 01:59, Taylor R Campbell wrote: > Date: Fri, 10 Dec 2010 17:40:32 -0500 > From: John Cowan <[email protected]> > > I have now added `current-jiffy` for elapsed time. > > This doesn't help. It doesn't give me a TAI clock. It's also not > clear to me what good jiffies are instead of seconds, or even how to > find jiffies on Unix systems.[*] > > I recommend a procedure (SECONDS-SINCE-UTC-EPOCH) that returns the > number of SI seconds that have elapsed since 1972-01-01T00:00:00Z.
This would be good. I've always felt that *local* concepts such as daily/annual cycles and colour and so on shouldn't be part of the foundation we build software systems on - not so much that we might one day write software for aliens, as that we very often write software for *machines*, that does things like process control; interfacing with humans occurs at the edge of such systems. Yes, in a calendar app, you'll need to work with dates. So in general, you need both date-oriented time and physics-oriented time in a general purpose computer system. In separate optional modules, so implementations can provide what they can, and applications can require what they need. ABS -- Alaric Snell-Pym http://www.snell-pym.org.uk/alaric/ _______________________________________________ Scheme-reports mailing list [email protected] http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports
