Document use cases for nanosecond resolution about proposal-temporal HOT 3 CLOSED

There are several use cases. The main one, however, is that of interoperability. JavaScript interacts with data from many other platforms. We should be able to round-trip data that contains nanoseconds without any truncation or lossyness. This also helps for platforms that present data with other sub-millisecond units, such as microseconds or the 100-ns "ticks" used in .NET.

I'll add some more as I come across them. Do understand that we are talking about the case for this precision, which is a separate concept from accuracy. Only the host environment can address accuracy, and it's likely to vary significantly across hardware and OS.

from proposal-temporal.

Are you concerned with nanosecond precision or nanosecond resolution?

Ideally, one would have both but it seems to me that resolution is a characteristic of the temporal time types while precision is a characteristic of the source of the value. To my sensibilities, a single value has resolution and accuracy but precision is an attribute of a time source and can only be experienced or assessed with a collection of values. Or am I missing your point or meaning?

ntp.org has an overview of clock quality that seems relevant, though their description of precision seems conflicted, with two inconsistent definitions. I also quite like the Precision, Accuracy and Resolution page by Dave Tutelman.

I was long frustrated by systems that had only one second resolution and, with the speed of computers these days, now even millisecond resolution seems a handicap. There can be many events in a millisecond and without finer resolution, no way to record when they happened and put them in order. Not that the accuracy and precision of clocks on different systems are not still an even greater problem but it is nice to have data types that aren't the limiting factor.

from proposal-temporal.

@ig3 - We are primarily talking about the resolution of the data supported in the data structures. I have updated the title of this issue accordingly.

Using the definitions from Dave's page, we aren't really in a position to address precision or accuracy at all. Those are qualities of the host environment. The best we can do is to offer a data structure that can hold data with nanoseconds without losing them, and to expose any underlying functionality for getting the current system time with the highest resolution possible.

from proposal-temporal.