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2591 :: macro problem

• doggy (orginal) [2016-10-24T05:58:19+02:00] view original

  proc test2(l：NimNode):NimNode=

  ...

  macro test(l:typed):untyped=

  test2(l)

  newVarStmt(newIdentNode("res"), newCall(...))) //...is a function return a val of type M

  and when I call test(res) the res's real type is nnkSym -> nnkCall but, what I want res's type is M(nnkObjConstr) So is there any solation?

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• Araq (orginal) [2016-10-24T10:05:29+02:00] view original

  Apparently you ask about newTree(nnkObjConstr, ...), but please be clearer. :-)

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• doggy (orginal) [2016-10-24T19:52:41+02:00] view original

  alright, I give an example code:

  import macros, strutils
  
  var t {.compileTime.} = false
  
  proc test2(arg: NimNode):NimNode =
      echo "get result:" & treeRepr(arg)
      var a = getImpl(arg.symbol)
      #[
      if t == false :        echo "inside call begin"        var stmt = newStmtList(newVarStmt(newIdentNode("res2"), newCall(newIdentNode("test3"), newIntLitNode(1024))), newNimNode(nnkDiscardStmt).add(newCall(newIdentNode("test1"), newIdentNode("res2"))))
          result = stmt
          echo result.repr
          echo "inside call end"
          
          t = true
      ]#
      echo "get result2:" & treeRepr(a)
  
  macro test1* (arg : typed):untyped =
      result = test2(arg)
  
  type m = object
      a:int
      b:string
  proc test3(c : int):m =
      m(a:c, b:"asdasd")
  var res = test3(100)
  ###here I just want to get res as [m(a:100, b:"asdasd")], not a [call]
  test1(res)
  Run

  So, I want to use test1 to get res's value and do something, but from this code, I just got the

  get result:Sym "res"
  get result2:Call
    Sym "test3"
    IntLit 100
  Run

  So...Do u have any idea to solve this?

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