RFC: Time Library 0.1

Ashley Yakeley ashley at semantic.org
Wed Jul 6 04:02:54 EDT 2005

In article <Pine.LNX.4.60.0507051133050.24946 at hermes-1.csi.cam.ac.uk>,
 Tony Finch <dot at dotat.at> wrote:

> Is midnight 00:00 or 24:00?

Midnight is just midnight. The formatTime function will show it as 

> I think that pretending to support UT1 and TAI on most computers is too
> much of a fiction to be justifiable in a library of this kind. The vast
> majority of programs don't need absolute time to sub-second accuracy, and
> the vast majority of operating systems can't even support UTC leap seconds
> correctly. Time specialists do need this stuff, but they'll have their own
> code.

TAI and leap-seconds are all in System.Time.TAI, so you don't have to 
worry about it.

UT1 is necessary for historical time, since back-extending UTC is 
pointless and back-extending TAI completely hopeless. The UT1 type is 
really simple (ModJulianDate, a synonym for Rational that counts days), 
so there's not much extra complication.

Ashley Yakeley, Seattle WA

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