template <class BidirectionalIterator, class Allocator>
bool operator==(const match_results<BidirectionalIterator, Allocator>& m1,
const match_results<BidirectionalIterator, Allocator>& m2);
template <class BidirectionalIterator, class Allocator>
bool operator!=(const match_results<BidirectionalIterator, Allocator>& m1,
const match_results<BidirectionalIterator, Allocator>& m2);