Can I get the time "Duration" in "nsecs" acurracy?

[Bruce Carneal]

On Saturday, 10 July 2021 at 01:11:28 UTC, Steven Schveighoffer 
wrote:
> 
>
> You can get better than hnsecs resolution with 
> `core.time.MonoTime`, which can support whatever the OS 
> supports.
>
> However, `Duration` and `SysTime` are stored in hnsecs for a 
> very specific reason -- range. Simply put, if you have a 64-bit 
> integer, and you picked nanoseconds as the unit, you can store 
> only 585 years of range. 10 ns gives you 5850 years, and 100 ns 
> gives you 58k years. That should be good enough for all but the 
> most esoteric calculations (given that a `Duration` is signed, 
> this gives a range of roughly -29k years to 29k years).
>
> Note also that hnsecs is the base unit for Windows high 
> precision clocks, though their epoch is year 1600 instead of 
> year 0.

Nice summary. hnsecs is a little weird but defensible given the 
range argument.

Down the road we might add a nanosecond timeline abstraction 
based on TAI with zero set to 1972 (when UTC was aligned with TAI 
IIUC).  Range issues could be addressed by animating the long 
dormant cent.  Any precision issues could be handled with fixed 
point pairs.

Doubles across the same timeline would work for casual 
applications.