The functor can change non-key fields of the \p item; however, \p func must guarantee
that during changing no any other modifications could be made on this item by concurrent threads.
- You can pass \p func argument by value or by reference using \p std::ref.
-
Returns std::pair<bool, bool> where \p first is \p true if operation is successfull,
\p second is \p true if new item has been added or \p false if the item with \p key
already is in the set.
\endcode
where \p item is the item found, \p key is the <tt>find</tt> function argument.
- You can pass \p f argument by value or by reference using \p std::ref.
-
The functor can change non-key fields of \p item. Note that the functor is only guarantee
that \p item cannot be disposed during functor is executing.
The functor does not serialize simultaneous access to the set \p item. If such access is