On 19 Sep 2014, at 14:59, Esteban A. Maringolo <[email protected]> wrote:
> 2014-09-19 9:16 GMT-03:00 Sven Van Caekenberghe <[email protected]>: >> 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). > > +1 > >> January 30 + 1 month ? >> January 31 + 1 month ? >> Februari 29 2004 + 1 year ? >> >> And given all sorts of cleverness, will basic math rules still work ? >> >> A +B = B + A >> A + B = C => C - B = A > > Pharo Date/DateAndTime are incremental[1], then all this > week/month/year operations will simply add/subtract the increment from > epoch. > > The only way to do this in a deterministic way is to have a field based Date. Saying that it is not deterministic is a bit harsh ;-) > Regards! > > Esteban A. Maringolo > > [1] http://www.w3.org/TR/2005/NOTE-timezone-20051013/#d2e310 Very interesting link, really useful - Thx.
