std::insert_iterator::operator*
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                    < cpp | iterator | insert iterator
                    
                                                            
                    | insert_iterator& operator*(); | ||
Does nothing, this member function is provided to satisfy the requirements of OutputIterator.
It returns the iterator itself, which makes it possible to use code such as *iter = value to output (insert) the value into the underlying container.
Parameters
(none)
Return value
*this