[Python-Dev] PEP 410 (Decimal timestamp): the implementation is ready for a review (original) (raw)

Guido van Rossum guido at python.org
Wed Feb 15 17:39:45 CET 2012

I just came to this thread. Having read the good arguments on both sides, I keep wondering why anybody would care about nanosecond precision in timestamps. Unless you're in charge of managing one of the few atomic reference clocks in the world, your clock is not going to tell time that accurate. (Hey, we don't even admit the existence of leap seconds in most places -- not that I mind. :-)

What purpose is there to recording timestamps in nanoseconds? For clocks that start when the process starts running, float is (basically) good enough. For measuring e.g. file access times, there is no way that the actual time is know with anything like that precision (even if it is recorded as a number of milliseconds -- that's a different issue).

Maybe it's okay to wait a few years on this, until either 128-bit floats are more common or cDecimal becomes the default floating point type? In the mean time for clock freaks we can have a few specialized APIs that return times in nanoseconds as a (long) integer.

-- --Guido van Rossum (python.org/~guido)

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