-- repmin example

syntax { finMin |- t : !gathMin ~> !t' };
syntax node { 1 :-: 2 };
syntax leaf { <1> };

let testtree = ((<8>) :-: (<5>)) :-: ((<3>) :-: (<9>));

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

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


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