Root Class
Any methods
tree TOSTRING // x.toString
tree GETCLASS // x.getClass
tree IS typ // x.isInstanceOf[Int]
tree AS typ // x.asInstanceOf[Int]
Any operators
lhs ANY_== rhs // ==
lhs ANY_!= rhs // !=
lhs ANY_-> rhs // ->
AnyRef operators
lhs OBJ_EQ rhs // eq
lhs OBJ_NE rhs // ne