Thorsten Ottosen wrote:
Shunsuke Sogame wrote:
Hi,
If a pointer container holds noncopyable objects, the iterators seem not to meet ReadableIteratorConcept whose 'value_type' must be CopyConstructible?
From
http://www.boost.org/libs/iterator/doc/new-iter-concepts.html#readable-itera...
it seems that the iterator type itself must be CC and CA. For a given iterator a, *a must be convertible to iterator_traits<X>::value_type (we'll use T for this below).
For pointer containers, this currently poses quite a problem because of its indirected interface: the conversion could succeed if T was defined as iterator_traits<X>::reference, but the ReadableIteratorConcept does not allow T to be a reference type.
The only thing I can come up with is that pointer container iterators does not satisfy the ReadableIteratorConcept, but only the ReadableLvalueIteratorConcept.
Does that make sense?
LvalueIteratorConcept? It seems to be right. I overlooked 'Readable' and 'Lvalue' is orthogonal. A concept checker of my alogorithm should have been something like... boost::function_requires< boost_concepts::ReadableIteratorConcept<Iterator> *OR* boost_concepts::LvalueIteratorConcept<Iterator> >(); I don't know how to OR, though :-( Thanks! -- Shunsuke Sogame