----Original Message---- From: boost-bounces@lists.boost.org [mailto:boost-bounces@lists.boost.org] On Behalf Of John Maddock Sent: 16 March 2006 10:24 To: boost@lists.boost.org Subject: Re: [boost] distance operation (24.3.4)

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const char * is not a random access iterator because it is not an output iterator, therfore not a forward iterator, therefore not a bidirectional iterator and therefore not a random access iterator - 24.1

The iterator categories are defined in 24.1, iterator traits is simply an aid to deducing that category for a given iterator. As it happens, you have found a defect in the standard, that itetarator_traits< const T * > reports the wrong category. Of course my preferred fix would be to find a better category definition so that 24.3.1.2 was correct <g>

Hold your horses here: surely const char* most certainly *is* a random access iterator, albeit an immutable one. I don't see anything in 24.1 that requires OutputIterator semantics for anything except, well output iterators :-)

Waiting to be shot down in flames yours, John.

Section 24.1, paragraph 3 says: "Forward iterators satisfy all the requirements of the ... output iterators" On the other hand, paragraph 4 says "A forward ... iterator can ... be ... constant". "Constant iterators do not satisfy the requirements for output iterators". I think there is a clear defect in the standard here.

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