On Tue, Oct 30, 2012 at 2:55 AM, Paul Rubin <no.email@nospam.invalid> wrote: > andrea crotti <andrea.crott...@gmail.com> writes: >> and we want to change its state incrementing the number ... >> the immutability purists would instead suggest to do this: >> def increment(self): >> return NumWrapper(self.number + 1) > > Immutability purists would say that numbers don't have "state" and if > you're trying to change a number's state by incrementing it, that's not > immutability. You end up with a rather different programming style than > imperative programming, for example using tail recursion (maybe wrapped > in an itertools-like higher-order function) instead of indexed loops to > iterate over a structure.
In that case, rename increment to next_integer and TYAOOYDAO. [1] You're not changing the state of this number, you're locating the number which has a particular relationship to this one (in the same way that GUI systems generally let you locate the next and previous siblings of any given object). ChrisA [1] "there you are, out of your difficulty at once" - cf WS Gilbert's "Iolanthe" -- http://mail.python.org/mailman/listinfo/python-list
