upgrade to go 1.18, use generics

irc/utils/types.go

@@ -5,13 +5,25 @@ package utils
 
 type empty struct{}
 
-type StringSet map[string]empty
+type HashSet[T comparable] map[T]empty
 
-func (s StringSet) Has(str string) bool {
-	_, ok := s[str]
+func (s HashSet[T]) Has(elem T) bool {
+	_, ok := s[elem]
 	return ok
 }
 
-func (s StringSet) Add(str string) {
-	s[str] = empty{}
+func (s HashSet[T]) Add(elem T) {
+	s[elem] = empty{}
+}
+
+func (s HashSet[T]) Remove(elem T) {
+	delete(s, elem)
+}
+
+func CopyMap[K comparable, V any](input map[K]V) (result map[K]V) {
+	result = make(map[K]V, len(input))
+	for key, value := range input {
+		result[key] = value
+	}
+	return
 }