You could use Month class>>#daysInMonth:forYear: Which I think does what you want already. stepharo wrote

Hi

I started to write a little utility to generate bills.

And I need to know the number of days in a month and I was surprised that

(Month month: 2) daysInMonth returns 28 because we do not know :)

So I thought that I was obviously wrong and I should use

(Year year: 2016) daysInMonth

> "#(31 28 31 30 31 30 31 31 30 31 30 31)"

:(

When I look at the implementation this is clear that it is wrong

daysInMonths ^ Date daysInMonth

totally not aware of the year.

I think that daysInMonths should use DateAndTime creating a dummy date for each month and using asMonth daysInMonth

(DateAndTime year: 2016 month: 2 day: 3) asMonth daysInMonth

> 29

Year >> daysInMonth: aMonthNumber "Returns the days in month for a given month"

<expr: #(#(#Year #year: 2016) #daysInMonth: 2) result: 29> ^ (DateAndTime year: self year month: aMonthNumber) asMonth daysInMonth

I extended the class with some more practical methods. What do you think? I should push them to pharo?

I was surprised that the library was not that good.

Stef

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