Boost C++ Libraries: Ticket #1860: zip_iterator::value_type should not be reference

attachment set

anonymous — Thu, 24 Apr 2008 18:39:47 GMT

attachment → zip_iterator.diff

Steven Watanabe — Fri, 21 Aug 2009 19:33:16 GMT

This looks like a duplicate of #973.

Mathias Gaunard — Fri, 28 Aug 2009 14:29:10 GMT

Is there any reason not to merge this patch? zip_iterator compiles the above code but produces erroneous output, that's a pretty important bug.

If there is a problem with this patch, please let me know what needs to be improved.

owner changed

Dave Abrahams — Sat, 28 Nov 2009 18:23:46 GMT

owner changed from Dave Abrahams to Mathias Gaunard

One reason is that I don't have a testcase that is actually reliable. You see, zip_iterator can't be a legit C++03 Forward Iterator, since its reference type is not a real reference. Therefore, the standard library has a right to refuse to compile the example you gave even without the patch. It may work on your installation and legitimately break somewhere else.

So, if you could build a testcase that doesn't rely on strict Forward Iterator conformance, but instead captures the assumptions that your std::sort implementation is making, that make this work, I'd be more than happy to accept the patch as a QOI improvement.

A smaller issue is the definition of iterator_value_type is redundant with iterator_value in <boost/iterator/iterator_traits.hpp>

Thanks for your efforts and patience on this one.

status changed; resolution set

dtrebbien@… — Sun, 28 Nov 2010 00:11:04 GMT

status new → closed
resolution → duplicate