On 19.09.2014, at 14:16, Sven Van Caekenberghe <s...@stfx.eu> wrote:
> Part of that is in > https://pharo.fogbugz.com/f/cases/13229/Year-arithmetic-broken > > Furthermore, I am not so sure all this is a good idea, year/month durations > are not constants and are dealt with differently in many context (say the > financial world). > > January 30 + 1 month ? > January 31 + 1 month ? Issue 13299 doesn’t change that (I don’t know about the other change). There is still only the Month object which knows its number of days, so a month will always be used in a defined context. > Februari 29 2004 + 1 year ? This one is hard and the change in issue 13299 does indeed make the assumption that February 29 2004 + 1 year = February 28 2005. One might argue that is should be March 1. But: that is also the assumption the *current* implementation makes, so no change there. > > And given all sorts of cleverness, will basic math rules still work ? > > A +B = B + A > A + B = C => C - B = A > > On 19 Sep 2014, at 13:54, Sean P. DeNigris <s...@clipperadams.com> wrote: > >> From >> http://forum.world.st/Next-version-of-Date-DateAndTime-and-Duration-API-updates-td4778871.html >> : >> >> Now in the InBox: >> KernelTests-cbc.278.mcz >> Kernel-cbc.871.mcz >> The tests add in test for expected Duration addition and subtraction from >> each other, including the new GenericMonth and GenericYear, and the very new >> GenericDuration. It also adds a few more tests for LeapYear tests with >> adding years to them. >> >> The test are still based on what it currently does, with the exceptions >> listed previously (I haven't really changed any to expect failures, as has >> been suggested - that will come shortly. For now, I want to try to cause >> little to no changes o expected behavior first - just new behavior for now). >> >> Kernel adds the GenericDuration, and handles adding and subtracting >> GenericMonth, GenericYear, and GenericDurations togeher in a rational way. >> This involves turning + and - in Durations into a double-dispatch so that it >> will work. >> >> There are no comments yet in these classes - they will be there before the >> weekend is over at the latest. >> >> Any comments are more than welcome. >> >> -cbc >> >> >> >> ----- >> Cheers, >> Sean >> -- >> View this message in context: >> http://forum.world.st/Interesting-Date-Time-Thread-on-Squeak-Dev-tp4778652p4778945.html >> Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com. >> > >
