"Fredrik Lundh" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Steven Bethard wrote: > > >>>>>a = 1, 2, 3 > >>>>>b = a[:] > >>>>>a is b > >> True > > > > My impression was that full tuple copies didn't actually copy, but that > > slicing a subset of a > > tuple might. Not exactly sure how to test this, but: > > > > py> a = 1, 2, 3 > > py> a[:2] is a[:2] > > False > > yup. and to figure out why things are done this way, consider this case: > > >>> a = give_me_a_huge_tuple() > >>> len(a) > (a rather large number) > >>> b = a[:2] > >>> del a > > (IIRC, I proposed to add "substrings" when I implemented the Unicode string > type, but that idea was rejected, for the very same "and how do you get rid of > the original object" reason) > > </F>
Fair enough. So perhaps the question is whether such cases are more regular than something like: a = give_me_a_huge_tuple() slices = [a[i:j] for i in xrange(len(a)) for j in xrange(i+1, len(a)+1)] George -- http://mail.python.org/mailman/listinfo/python-list
