std::regex_token_iterator<BidirIt,CharT,Traits>:: operator++, operator++ (int)

From cppreference.com
regex_token_iterator & operator ++ ( ) ;
(since C++11)
regex_token_iterator operator ++ ( int ) ;
(since C++11)

Advances the iterator on the next sub match.

If * this is a suffix iterator, sets * this to an end-of-sequence iterator.

Otherwise, if N + 1 < subs. size ( ) , increments N and sets result to the address of the current match.

Otherwise, sets N to 0 and increments position . If position is not an end-of-sequence iterator the operator sets result to the address of the current match.

Otherwise, if any of the values stored in subs is equal to - 1 and prev - > suffix ( ) . length ( ) is not 0 the operator sets *this to a suffix iterator that points to the range [ prev - > suffix ( ) . first , prev - > suffix ( ) . second ).

Otherwise, sets * this to an end-of-sequence iterator.

The behavior is undefined if the iterator is end-of-sequence iterator.

Parameters

(none)

Return value

1) * this
2) The previous value of the iterator.