"Howard Hinnant" <hinnant@twcny.rr.com> wrote in message news:2c82a06f47cb364610ee3f054122873e@twcny.rr.com... | On Jun 15, 2005, at 11:58 AM, David Abrahams wrote: | | > "Thorsten Ottosen" <nesotto@cs.auc.dk> writes: | > | >> "David Abrahams" <dave@boost-consulting.com> wrote in message | >> news:uk6kws88y.fsf@boost-consulting.com... | >> | >> | If someone would clearly and succinctly spell out the question, I'd | >> be | >> | happy to. | >> | >> should one be able to add, subtract, and compare mutable random access | >> iterators with | >> random access const_iterators provided they point to the same | >> container? | > | > There is no requirement that it be possible, and many early STL | > implementations failed to make it possible. It's generally regarded | > as a poor QOI that doesn't allow it. That capability is one of the | > things that iterator_facade and iterator_adaptor make easy. | | Umm... and you helped me with the wording to require this for C++0X (it | is already in the WP): | | http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#179 Thanks! I'm only missing to make operator- to be free-standing. I will update that as well. -Thorsten