void func( value_type& val );
\endcode
where \p val is the item inserted.
- While the functor \p f is working the item \p val is locked.
+ While the functor \p f is called the item \p val is locked so
+ the functor has an exclusive access to the item.
The user-defined functor is called only if the inserting is success.
*/
template <typename Func>
refer to the same thing.
The functor may change non-key fields of the \p item.
- While the functor \p f is working the item \p item is locked.
+ While the functor \p f is working the item \p item is locked,
+ so \p f has exclusive access to the item.
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