c++ - Checking if an iterator is valid -

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is there way check if iterator (whether vector, list, deque...) (still) dereferencable, i.e. has not been invalidated?

i have been using try-catch, there more direct way this?

example: (which doesn't work)

list<int> l; (i = 1; i<10; i++) {     l.push_back(i * 10); }  itd = l.begin(); itd++; if (something) {     l.erase(itd); }  /* now, in other place.. check if itd points somewhere meaningful */ if (itd != l.end()) {     //  blablabla }

i assume mean "is iterator valid," hasn't been invalidated due changes container (e.g., inserting/erasing to/from vector). in case, no, cannot determine if iterator (safely) dereferencable.


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