diff --git a/baselib.go b/baselib.go
index aa2c08a9..7572d696 100644
--- a/baselib.go
+++ b/baselib.go
@@ -410,7 +410,7 @@ func baseToNumber(L *LState) int {
 		L.Push(lv)
 	case LString:
 		str := strings.Trim(string(lv), " \n\t")
-		if strings.Index(str, ".") > -1 {
+		if strings.ContainsRune(str, '.') {
 			if v, err := strconv.ParseFloat(str, LNumberBit); err != nil {
 				L.Push(LNil)
 			} else {
diff --git a/parse/lexer.go b/parse/lexer.go
index c20a0bdd..0f1cae47 100644
--- a/parse/lexer.go
+++ b/parse/lexer.go
@@ -512,7 +512,7 @@ func dump(node interface{}, level int, s string) string {
 		tt := rt.Elem()
 		indicies := []int{}
 		for i := 0; i < tt.NumField(); i++ {
-			if strings.Index(tt.Field(i).Name, "Base") > -1 {
+			if strings.Contains(tt.Field(i).Name, "Base") {
 				continue
 			}
 			indicies = append(indicies, i)