Pensieri di un lunatico minore

A pattern for time travel

One of hte hardest things to deal with in computer systems is time. While time may be monotonic in the abstract, unfortunately when humans get involved we get the morass of time-zones, time-saving silliness and other things that complicate the ability to work with information that exists temporally. As an off-shoot of a discussion on the Seaside mailing list about money (another strange thing to deal with), was a pointer by the taltented Cees de Groot to an excellent paper: Time Travel: A Pattern Language for Values that Change (PDF). Written by some very smart people it details how to deal with the thorny issue of values and time. The examples are written in Smalltalk, but I suspect most anyone can read them.