On Oct 12, 12:32 pm, Mensanator <mensana...@aol.com> wrote: > On Oct 12, 1:02 pm, John Reid <j.r...@mail.cryst.bbk.ac.uk> wrote: > > Mensanator wrote: > > > On Oct 12, 3:36 am, greg <g...@cosc.canterbury.ac.nz> wrote: > > >> Mensanator wrote: > > >>> while not done: > > >>> ... > > >>> if n==1: done = True > > >>> ... > > >> Seems to me that 'while not done:' is no better than > > >> 'while True:', because in both cases you have to look > > >> inside the loop to find out what the exit condition > > >> is. > > > >> Using a more meaningful name for the flag can help, > > >> but you can't teach someone that just by giving them > > >> an overly simplified rules such as "never use > > >> while True:". They'll probably just replace it with > > >> 'while not done:' and think they've improved things, > > >> without ever really understanding the issue. > > > > You're missing the point. It's not that you have to > > > look inside for the terminating condition. It's that > > > you don't need a break. > > > Nothing wrong with a having a break IMHO. > > My opinion is that there is everything wrong with > having a break. I don't think I have ever used one, > I write code that doesn't depend on that crutch. > > > > > while not done: > > > seems very dangerous to me as you'd have to > > > del done > > > before writing the same construct again. That's the sort of thing that > > leads to errors. > > Duh. I won't write silly code like that either. > If I need more than one loop structure then I'll > do something like > > while not done_with_this > > while not done_with_that > > Besides, since I _always_ initialize the flag > before entering a loop, the flag can be reused > and doesn't have to be deleted (as long as the > loops aren't nested). And since I don't use goto, > there's no chance the initialization can be avoided. > > The best way to avoid the pitfalls of spaghetti > code is to not write it in the first place.
How do you manage code where you need to drop out of a neatly written for or while loop early? I don't use break frequently, but just like gotos, it does have it's place in well written code. Glad to hear, by the way, that you don't use gotos in Python. =D Garrick -- http://mail.python.org/mailman/listinfo/python-list
