Is there a simple way to detect when a set insert does not occur because the item being inserted already exists in the set? For example, I'd like to display a message to the user that shows the insert failure so that they can find and remove the duplicates in their data more easily. Here's some pseudo code to demonstrate what I'd like to do:
// show user the failed item
There is this
insert signature in
pair<iterator,bool> insert ( const value_type& x );
second of the returned pair, should be set to true if inserted successfully.