LetExp([
 TypeDec[
  (rectype,
   RecordTy[
    (name,true,string),
    (id,true,int)])],
 VarDec(rec1,true,NONE,
  RecordExp(rectype,[
   (name,
    StringExp("Name")),
   (id,
    IntExp(0))]))],
 AssignExp(
  FieldVar(
   SimpleVar(rec1),
   nam),
  StringExp("asd")))