-- repmin example

syntax { finMin |- t : !gathMin ~> !t' };

let testtree = node (node (leaf 8) (leaf 5)) (node (leaf 3) (leaf 9));

let repmin = derivation inputs t
                        inputs finMin visit disperse
                        outputs gathMin
                        outputs t' visit disperse
  { branch node:
      establish repmin m |- l : lm ~> l';
      establish repmin m |- r : rm ~> r';
      --------
      establish m |- node l r : min lm rm ~> node l' r';

    branch leaf:
      --------
      establish min |- leaf i : i ~> leaf min;
  };


derivation inputs args outputs t
{ branch main:
    establish repmin m |- testtree : m ~> this.t;
}