Chris Muller
2018-10-22 21:30:52 UTC
Hi Dave,
Thanks for making UTCDateAndTime available on SqueakMap that "just
works" -- not having to go research how to properly install it left me
some time to actually start looking at it today.
A cursory look reveals that, at least functionally, everything appears
to be essentially the same as original Chronology except the on-going
million-dollar question:
What are the point-in-time endpoints of a timespan
identified by a particular "Date"?
There are two reasonable answers to this question:
1) "local" e.g., a period that begins from 12am to
11:59:59.999999 of my LOCAL time,
or 2) "global" e.g., a period that begins from 12am to
11:59:59.999999 of UTC (offset 0).
We already know that original Chronlology supports ability for
applications to represent their Dates either way. What about
UTCDateAndTime? When I do:
DateAndTime now asDate = Date today
I get "true", even though MY 22-Oct-2018 begins and ends at a
different point-in-time than those in the UTC timezone..
I realize most applications want a canonical representation of Dates,
but where does this leave the timespan use-cases? Are they even
possible at all? What if I truly need the same local representation
of 22-Oct-2018 that everyone else recognizes in my
Thanks for making UTCDateAndTime available on SqueakMap that "just
works" -- not having to go research how to properly install it left me
some time to actually start looking at it today.
A cursory look reveals that, at least functionally, everything appears
to be essentially the same as original Chronology except the on-going
million-dollar question:
What are the point-in-time endpoints of a timespan
identified by a particular "Date"?
There are two reasonable answers to this question:
1) "local" e.g., a period that begins from 12am to
11:59:59.999999 of my LOCAL time,
or 2) "global" e.g., a period that begins from 12am to
11:59:59.999999 of UTC (offset 0).
We already know that original Chronlology supports ability for
applications to represent their Dates either way. What about
UTCDateAndTime? When I do:
DateAndTime now asDate = Date today
I get "true", even though MY 22-Oct-2018 begins and ends at a
different point-in-time than those in the UTC timezone..
I realize most applications want a canonical representation of Dates,
but where does this leave the timespan use-cases? Are they even
possible at all? What if I truly need the same local representation
of 22-Oct-2018 that everyone else recognizes in my