library-calls-adjudicator.mvir

// in application module
module Payments {
  import 0x30.Adjudicator;
  public validTransition(s1, s2) {
  // implement app-specific transition logic
  }
  
  public respond(R#Adjudicator.T adjudicator, V#State s1, V#State s2) {
    assert(validTransition(s1, s2));
    Adjudicator.respond(move(adjudicator), s1, s2);
  }
  
  // ... (other code not shown) ...
}

// in adjudicator module
module Adjudicator {
  public respond(Adj adjudicator, State s1, State s2) {
    // framework checks 
    // … (not shown) …
    
    // app-specific checks
    let appDef = getAppDefinition(copy(s1));
    // only allow response if the app library is calling us
    assert(appDef == get_calling_module());

    // if all checks pass, cancel the challenge
    cancel_challenge(move(adjudicator));
   }
  }
  
  // ... (other code not shown) ...
}