Boost logo

Boost :

From: Hervé Brönnimann (hervebronnimann_at_[hidden])
Date: 2007-11-13 02:08:09


Ben: Before you do any substantial work, please check my proposal. I
have tried to provide background / explanations, and a set of
coherent interfaces. Please look at:

http://photon.poly.edu/~hbr/boost/combinations.html

The code in the .hpp (linked) is only temporary and not debugged. I
am in the process of writing test cases. I'm happy to send it to you
too... Keep in mind it is work in progress. I have a job and am
spending far too much time on this at the moment :)
--HB

PS: I am not sure about the Incrementor/Decrementor interfaces,
unless I can come up with a convincing example where the underlying
type is not int and does not have operator++ and operator--, but it
still makes sense to count with it...

On Nov 13, 2007, at 1:50 AM, Ben Bear wrote:

> 2007/11/13, Hervé Brönnimann <hervebronnimann_at_[hidden]>:
>> 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.
> _______________________________________________
> Unsubscribe & other changes: http://lists.boost.org/mailman/
> listinfo.cgi/boost


Boost list run by bdawes at acm.org, gregod at cs.rpi.edu, cpdaniel at pacbell.net, john at johnmaddock.co.uk