Tim, You might consider a full-fledged framework for it like Chalten: https://github.com/ba-st/chalten
I don't know how it handles timezones, because the age calculation might get trickier if you consider also the time of birth and you're querying it from a different timezone ;-) Regards! Esteban A. Maringolo 2017-07-21 6:09 GMT-03:00 K K Subbu <kksubbu...@gmail.com>: > I suppose no one needed it that badly ;-). Age is the difference in years > except when the given date's julian is less than self's julian when it is > less by 1, so the code can be simplified to: > > ^aDate year - self year - > (aDate dayOfYear < self dayOfYear) ifTrue: [ 1 ] ifFalse: [ 0 ]) > > BTW, the code has an off-by-one error. +1 should be dropped in first age > assignment. > > Regards .. Subbu > > > On Friday 21 July 2017 12:55 PM, Tim Mackinnon wrote: >> >> Yes that's a good solution, however I'm really surprised that with the >> plethora of dates, durations, timespans (we are well served with a very rich >> time and date domain) that this isn't already in the image? >> >> It seems very surprising. In fact the group I was working with (other >> language programmers) kept looking and looking for something as they felt >> certain they had overlooked it given all those promising classes. >> >> I'm curious why it's not in there? And would we also expect to find its >> equivalent on a timespan (maybe delegating back to this date method? This >> assumes that timespan can be fixed as it loses precision unexpectedly). >> >> Thanks for the reply. >> >> Tim >> >> >> >> Sent from my iPhone >> >>> On 21 Jul 2017, at 06:41, K K Subbu <kksubbu...@gmail.com> wrote: >>> >>> Date>>ageOn: aDate >>> " assert: (self <= aDate) >>> | age | >>> >>> age = aDate year - self year + 1. >>> aDate monthIndex < self monthIndex ifTrue: [ ^age - 1 ]. >>> (aDate monthIndex = self monthIndex and: [aDate dayOfMonth < self >>> dayOfMonth]) ifTrue: [ ^age - 1 ]. >>> ^age >>> >>> HTH .. Subbu >>> >>>> On Friday 21 July 2017 05:28 AM, Tim Mackinnon wrote: >>>> Hi - I just ran a great MobProgramming session with Smalltalk for the >>>> XProLo group - and there was lots of great feedback and questions, however >>>> one of them really got me thinking… >>>> We did a little exercise to create a Person class with name, dob - and >>>> then we TDD’d an age method… which seems simple on the surface but it gets >>>> to an interesting point - what about leap years? How old is someone on >>>> those >>>> years? >>>> I thought that our plethora of Date/Duration classes might handle this - >>>> but I couldn’t spot something obvious and was wondering if someone had a >>>> neat answer. >>>> Essentially if you try: >>>> age >>>> ^Date today - self dob >>>> You get a Duration, >>>> But there isn’t : >>>> ^(Date today - self dob) asYears >>>> There is is asDay >>>> ^(Date today - self dob) asDays >>>> But then can you really >>>> ^(Date today - self dob) asDays / 365) truncated >>>> But what about leap years… so >>>> ^(Date today - self dob) asDays / 365.25) truncated >>>> It all feels a bit inelegant and I suspect there is a better Smalltalk >>>> way that is eluding me? Any suggestions? >>>> Tim >>> >>> >>> >> >> > >
