Wrote 'reg.FindSubmatch()' which returns the leftmost match with submatches, renamed 'isValid' to 'IsValid' to export it, renamed 'ToString' to 'String'

cmd/main.go

@@ -137,7 +137,7 @@ func main() {
 					fmt.Fprintf(out, "Line %d:\n", lineNum)
 				}
 				for _, m := range matchIndices {
-					fmt.Fprintf(out, "%s\n", m.ToString())
+					fmt.Fprintf(out, "%s\n", m.String())
 				}
 				err := out.Flush()
 				if err != nil {