Thanks for your respose.You seem the type of return for getLHS() is Expr *,How can you get A form A[4].As far as I know ,I cann't get a std::string form such type as Expr *. -- View this message in context: http://clang-developers.42468.n3.nabble.com/getLHS-and-getRHS-tp4028364p4028366.html Sent from the Clang Developers mailing list archive at Nabble.com.