func (s *Set) Add(value interface{}) {
	s.Lock()
	defer s.Unlock()
	s.m[value] = struct{}{}
}
func (s *Set) Add(value interface{}) {
	s.Lock()
	defer s.Unlock()
	s.m[value] = struct{}{}
}
func ( s * Set ) Add ( value interface { } ) { s . Lock ( ) defer s . Unlock ( ) s . m [ value ] = struct { } { } }
// Add adds a value to the set.
Add adds a value to the set .