2007/11/13, Hervé Brönnimann <hervebronnimann@mac.com>:
Ben: the naming partial_permutation would be a very good idea. I like it. Am I correct that your (very cute!) idea would be extended to prev_ as follows:
bool next_partial_permutation(first, middle, last) { reverse (middle, last); return next_permutation(first, last); }
prev_partial_permutation ( { bool result = next_permutation(first, last);
oh, here should be:-) bool result = prev_permutation(first, last);
reverse (middle, last); return result; }
That's all good, then. BTW, you *should* assume that the client has already sorted the range. In other words, garbage in, garbage out, and that's OK. There's not reason to penalize those who keep their ranges sorted. It simply needs to be documented as a Requirement: and given again as a Post-condition: (since the functions maintain the sorted range invariant).
ok, I will prepare a resume source code that contains partial_permutation and combination, but without initializatons. It will be very simple, against gacap.