A simple set data structure in go.

set.go

package set

type Set map[interface{}]struct{}

func (this *Set) Contains(m *interface{}) (exists bool) {
  s := *this
  _, exists = s[m]
  return
}

func (this *Set) Remove(mems ...interface{}) (cnt int) {
  s := *this
  for m := range mems {
    if _, exists := s[m]; exists {
      delete(s, m)
      cnt++
    }
  }
  return
}

func (this *Set) Add(mems ...interface{}) (cnt int) {
  s := *this
  for m := range mems {
    if _, exists := s[m]; exists {
      s[m] = struct{}{}
      cnt++
    }
  }
  return
}