Rename Group.toString() to Group.String()

regex/matching.go

@@ -40,15 +40,15 @@ func (m Match) String() string {
 	for i, g := range m {
 		if g.IsValid() {
 			toRet += fmt.Sprintf("Group %d\n", i)
-			toRet += g.toString()
+			toRet += g.String()
 			toRet += "\n"
 		}
 	}
 	return toRet
 }
 
-// Converts the Group into a string representation:
-func (idx Group) toString() string {
+// String converts the Group into a string representation.
+func (idx Group) String() string {
 	return fmt.Sprintf("%d\t%d", idx.StartIdx, idx.EndIdx)
 }