Scala: Expand Macros at Runtime

Question

How can the AST be obtained for scala code after the macros have been expanded at runtime?

  // obtain toolbox
  val tb = runtimeMirror(getClass.getClassLoader).mkToolBox()
  // generate the AST
  val tree = tb.parse(<...source code using one or more macros...>)
  // let's look at the code
  println(show(tree))
  // let's see what the AST looks like
  println(showRaw(tree))
  // expand macros!
  xTreem = ?????
  // now let's look at the code and AST
  println(show(xTreem))
  println(showRaw(xTreem))
  // compile and...
  val f = tb.compile(xTreem)
  // ... execute
  f()

Thanks!

Answer 1

After digging around, I have not found a way to get the post-macro-expanded AST at runtime using the current experimental reflect and compiler API docs, but I can use the compiler option -Ymacro-debug-lite to print out each macro as it gets expanded at compile time. Also, there's scalamacros.org and scalameta.org which propose the next gen of AST inspection/manipulation and macros.