On Sun, 19 Jun 2011 15:56:27 +0300, Ethan Furman <ethan at stoneleaf.us> wrote: > Lie Ryan wrote: > >> def length(L): >> if not L: return 0 >> return 1 + length(cdr(L)) > > How is this different from regular ol' 'len' ? It's better, because len() can't overflow the stack. ;)