On Sun, Apr 20, 2014 at 12:05 PM, Harlan Harris <[email protected]> wrote:
> There are date/time-manipulation libraries where the difference between > two dates is a date-interval, stored just as the endpoints. This approach has some nice features, but I feel like it's just kicking the can down the road and not really solving the problem. There's still the question of what to do about this: date₁ + (date₂ - date₃). In what sense did you mean to take the interval? Since you're taking the difference and then adding it to a different starting point, you don't know what about that difference was relevant. You could require writing something like this: - date₁ + days(date₂ - date₃) - date₁ + weeks(date₂ - date₃) - date₁ + months(date₂ - date₃) - date₁ + years(date₂ - date₃) - date₁ + workdays(date₂ - date₃) - date₁ + interestdays(date₂ - date₃) etc., although at that point, it's not entirely clear how much going through an intermediary interval types is really buying you.
