let
  var a := exit(0)
  /*       ^ function.builtin */

  primitive exit(ret: int) /* Shadowing the prelude-included built-in */

  var b := exit(0)
  /*       ^ function */

in
  exit(1);
  /* <- function */

  print("shadowing is fun");
  /* <- function.builtin */

  b := print
  /*   ^ variable */
end