resource buf (c) [if c==NULL then emp else emp] { c = NULL; }

put(x) [x|->] {
  with buf when (c==NULL) { c = x; }
} [x|->]

get(y;) [emp] {
  with buf when (c!=NULL) { y = c; }
} [emp]


putter() {
  local x;
  x = new();
  put(x);
  dispose x;
}

getter() {
  local y;
  get(y;);
  /* use y, but not its contents */
}

main() {
  putter() || getter();
}