How to transform statements in clang?

Hi All,

I have posted some questions about AST tree transformation before a week, no reply though. I have got problems while am trying to do transformation at different levels. Is TreeTransform.h file helpful for tree transformation? Let’s consider one example: transform for statement to while statement on AST. How can I achieve this task? Should I use TreeTransform.h file for this task? let me the steps and the way to to implement it. Your ideas are appreciated. thanks in advance.