Fix example to check the correct error value

_example/hook/hook.go

@@ -10,12 +10,12 @@ import (
 func main() {
 	sqlite3conn := []*sqlite3.SQLiteConn{}
 	sql.Register("sqlite3_with_hook_example",
-			&sqlite3.SQLiteDriver{
-					ConnectHook: func(conn *sqlite3.SQLiteConn) error {
-						sqlite3conn = append(sqlite3conn, conn)
-						return nil
-					},
-			})
+		&sqlite3.SQLiteDriver{
+			ConnectHook: func(conn *sqlite3.SQLiteConn) error {
+				sqlite3conn = append(sqlite3conn, conn)
+				return nil
+			},
+		})
 	os.Remove("./foo.db")
 	os.Remove("./bar.db")
 
@@ -54,7 +54,7 @@ func main() {
 		log.Fatal(err)
 	}
 
-	bk.Step(-1)
+	_, err = bk.Step(-1)
 	if err != nil {
 		log.Fatal(err)
 	}