On Fri, Nov 04, 2005 at 10:25:03PM -0300, Ricardo Fodra wrote: > Having a similar problem here: > > std::set<Person>* _family > ... > set<Person>::reverse_iterator iter = > _family->rbegin(); > ++iter; > > iter->setName(NULL); > > error: passing `const Person' as `this' argument of > `void Person::setName(char*)' discards qualifiers > > Why is the compiler thinking *iter is a "const > Person"? _family is not const and I'm not using a > const_reverse_iterator, although there are some > const_iterator in other parts of the code. > I think it's because you're not supposed to change the values stored in a set. Values are stored in a set using the operator<, so if you insert these names in a set, in this order: julia amanda gloria The set will store them internally like this, for fast retrieval: amanda gloria julia What if you change the first entry (amanda) to something else? The set will get lost: it will not be able to access its elements properly. The same happens to std::map.
