Rename types.go -> stringset.go for consistency

irc/utils/types.go

@@ -1,36 +0,0 @@
-// Copyright (c) 2020 Shivaram Lingamneni
-// released under the MIT license
-
-package utils
-
-type empty struct{}
-
-type StringSet map[string]empty
-
-func (s StringSet) Has(str string) bool {
-	_, ok := s[str]
-	return ok
-}
-
-func (s StringSet) Add(str string) {
-	s[str] = empty{}
-}
-
-func (s StringSet) Remove(str string) {
-	_, ok := s[str]
-	if ok {
-		delete(s, str)
-	}
-}
-
-func (s StringSet) Size() int {
-	return len(s)
-}
-
-func (s StringSet) Keys() (keys []string) {
-	for key := range s {
-		keys = append(keys, key)
-	}
-
-	return keys
-}