[Python-Dev] proposal: add basic time type to the standard library

Jeremy Hylton jeremy@alum.mit.edu
Thu, 7 Feb 2002 20:04:23 -0500


>>>>> "TP" == Tim Peters <tim.one@comcast.net> writes:

 TP> [Guido]
 >> I'm notoriously bad at channeling Jim. Nevertheless, I do recall
 >> him saying he wanted a lightweight time object.
 TP> Given that most mallocs align to 8-byte boundaries these days
 TP> (also true of pymalloc), it's impossible in reality to define a
 TP> smaller object than TimeStamp, provided it needs at least one
 TP> byte of info beyond PyObject_HEAD.
Also, it may not be necessary to have a TimeStamp object in ZODB 4.
There are three uses for the timestamp: tracking how recently an
object was used for cache evication, providing a last modified time to
users, and as a simple version number. 
In ZODB 4, the cache eviction may be done quite differently. The
version number may be a simple int. The last mod time will not be
provided for each object; instead, users will need to define this
themselves if they care about it. If they define it themselves,
they'd probably use a DateTime object, but we'd care much less about
how small it is.
Jeremy

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