Re: [Pharo-users] How to calculate someone's age elegantly? Does Duration work?

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