Erase without invalidating iterator Own horny chat
Concurrent operations (count, find, insert, and erase) invalidate any existing iterators that point into the table, An exception to this rule is that count and find do not invalidate iterators if no insertions or erasures have occurred after the most recent call to method rehash.
So, officially, you cannot traverse the hash map concurrently with deletion, insertion, and even to lookup operations in some cases.
The elements of STL containers are allowed to throw exceptions (except in destructors).
Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. IO Stack Exchange is a question and answer site for users and developers of distributed applications built on top of the blockchain operating system, EOS. Disclaimer: Be sure to block all other actions that would rely on the index, because data will invalidate during deletion and new data maybe deleted as well.
consider this pseudo code:- int Data Item::gen Derived () It selects a particular value in the mm and finds the lower and upper bounds on their location. -- Nick Keighley You did not find that statement because it it is false.
It then loops on all of them calculating a derived value for each. The standard says about associative containers [23.1.2/8]: The insert members shall not affect the validity of iterators and references to the container, and the erase members shall invalidate only iterators and references to the erased elements.
So, the bad news is that a concurrent erase operation can deallocate the item you are traversing through and you’ll get garbage or an access violation exception.
EDIT - Flooding/Recursive Improvement - High Speed Up and much more reliable I discovered that sometimes the deferred transactions get cancelled and it takes much time to delete all records. Sign up to join this community After I didn't find any other solution, I ended up with a sequential workaround which will delete all records by time.And you may add some authorization because not everybody should be able to delete all records.It hints that concurrent traversal is nevertheless possible if synchronized with concurrent erasure.Let’s see what can happen while traversing while insert and lookup operations are also occurring.