Kowalke Oliver (QD IT PA AS) escribió:
Hi, how can I ensure that an iterator is still valid (item was not removed from the index)?
Well, there is no legal way to determine whether an iterator is valid or not unless you already have this information from other sources (the state your program is in or other contextual info). The reason is that if you've got an invalid iterator you cannot do anything with it except assign it a new valid value: iterator it=cont.find(...); cont.erase(it); // "it" is now invalid *it; // ILLEGAL ++it; --it; // ILLEGAL it2=it; // ILLEGAL foo(it); // ILLEGAL, provided foo accepts "it" by value it=cont.find(...); // OK [That said, you can grossly abuse the functionality provided by Boost.MultiIndex's safe mode (http://www.boost.org/doc/libs/1_35_0/libs/multi_index/doc/tutorial/debug.htm... ) to check whether an iterator is valid, but this is totally non-recommendable as safe mode is a debugging aid and not program-level functionality, you really oughtn’t do it.] Joaquín M López Muñoz Telefónica, Investigación y Desarrollo