[feat] first version

pkg/set/set.go

@@ -0,0 +1,30 @@
+package set
+
+type Set map[interface{}]struct{}
+
+func NewSet() Set {
+	return make(map[interface{}]struct{})
+}
+
+func (s Set) Add(i interface{}) {
+	s[i] = struct{}{}
+}
+
+func (s Set) Has(i interface{}) bool {
+	_, ok := s[i]
+	return ok
+}
+
+func (s Set) Size() int {
+	return len(s)
+}
+
+func (s Set) Keys() []interface{} {
+	keys := make([]interface{}, 0)
+
+	for k, _ := range s {
+		keys = append(keys, k)
+	}
+
+	return keys
+}