y/iterator.go
func (s *MergeIterator) Rewind() {
	for _, itr := range s.all {
		itr.Rewind()
	}
	s.initHeap()
}
func (s *MergeIterator) Rewind() {
	for _, itr := range s.all {
		itr.Rewind()
	}
	s.initHeap()
}
func ( s * MergeIterator ) Rewind ( ) { for _ , itr := range s . all { itr . Rewind ( ) } s . initHeap ( ) }
// Rewind seeks to first element (or last element for reverse iterator).
Rewind seeks to first element ( or last element for reverse iterator ) .