Terry Reedy wrote: > "George Sakkis" <[EMAIL PROTECTED]> wrote in message > news:[EMAIL PROTECTED] > > Actually my initial motivation was not a huge tuple I had to slice many > > times. It was something much > > less extraordinarily unlikely, a recursive function with a sequence
> > parameter: > > > > def foo(sequence): > > # base_case > > # do_stuff() > > combine(foo(sequence[:n]), > > foo(sequence[n:])) > > > > Having each slice be a view of the original sequence instead of a fresh > > copy would be a Good Thing > > Why? To save time? memory? Either would require more that a few bytes per > slice. If they are, you can probably use virtual slices as follows. > > def foo(sequence): > def _foo(seq, start, stop) > # base_case > # do_stuff() > combine(_foo(seq, start, n), _foo(seq, n, stop)) > _foo(sequence, 0, len(sequence) > > In other words, if you don't really want slices copied out of the sequence, > then don't slice! Just use 2 ints to indicate the working region or view. > Both this and using a nested function with additional params are standard > techniques. This also works when the seq is mutable and you want changes > to the 'slice' to change the original, as in quicksort. > > Terry J. Reedy I would say these are standard *C/C++* techniques; slicing simplifies things and thus seems more 'pythonic' to me. George -- http://mail.python.org/mailman/listinfo/python-list
