!7

srecord ToParse(O text) {}
srecord StarPattern(O text) {}

cprint {
  delegate TransformationTrail to TransformersOnObjects.
  transient new TransformersOnObjects too;
  switchable long maxSteps = 1000;
  
  transient F1 starPatternWrapper;

  start-thread {
    S ruleText = [[LineByUser("a * is something like *") => Assumption("* is a noun")]];
    too.add(ToParse(ruleText));
    
    // unpack ToParse
    too.addTransformer(func(ToParse x) { x.text });

    too.addTransformer(f<S, O> splitAtDoubleArrow_pair);
    too.addTransformer(f<S, O> parseFunctionCall);
    too.addTransformer(f<S, O> unquote, f<S, S> quote);
    too.addTransformer(f<Pair, O> pairA);
    too.addTransformer(f<Pair, O> pairB);
    //too.addTransformer(f<S, Bool> isStarPattern);
    
    // Suggest enclosing a star pattern string with StarPattern()
    too.addTransformer(starPatternWrapper = func(S s) {
      isStarPattern(s) ? StarPattern(s) : null
    });
    
    // Reintegrate replaced star patterns into rule text
    too.addTransformer(func(StarPattern s) {
      print("Found StarPattern: " + s);
      Cl<TransformationTrail> trails = too.getTrailsBy(s, starPatternWrapper);
      fOr (TransformationTrail trail : trails)
        replaceInSource(s.text, trail.argument);
      null;
    });
      
    stepAllWithStats(too, maxSteps);
    too.printWithTrails();
  }
  
  // replace a in b inside of where a came from
  void replaceInSource(O a, O b) {
    print(formatFunctionCall replaceInSource(a, b));
    
    // Find trails of a
    Cl<TransformationTrail> trails2 = too.getTrails(a);
    
    fOr (TransformationTrail trail2 : trails2) {
      F1 back = too.getBackTransformer(trail2.transformer);
      print("  Path back: " + trail2 + " >> " + back);
      if (back != null)
        // Backtransform b and put in pool
        too.addObject(back.get(b), "replaceInSource");
    }
  }
}