!7

static Guesser best;
static double bestScore;
sS key = "verb";

concept Sentence {
  S text;
  SS data;
  
  S get(S s) { ret data.get(s); }
  S subject() { ret get("subject"); }
  S verb() { ret get(key); }
}

sclass Input {
  L<S> tok;
  IntRange subject;
  
  *() {}
  *(L<S> *tok, IntRange *subject) {}
}

Input > Example {
  new L<IntRange> verbs;

  *() {}
  *(L<S> *tok, IntRange *subject, L<IntRange> *verbs) {}
  
  toString {
    ret quote(joinWithSpaces(tok)) + " => " + map(verbs, func(IntRange r) { joinWithSpaces(subList(tok, r.start, r.end)) });
  }
}

abstract sclass GuesserBase {
  void learn(L<Example> material) {
    for (Example e : material) learn(e);
  }
  void learn(Example e) {}
}

abstract sclass Guesser extends GuesserBase {
  abstract L<IntRange> getVerbTokens(Input input);
}

Guesser > GWordAfterSubject {
  L<IntRange> getVerbTokens(Input input) {
    IntRange r = input.subject;
    ret r == null ? null : ll(intRange(r.end, r.end+1));
  }
}

p {
  loadConceptsFrom(#1008692);
  L<Example> material = learningMaterial();
  pnlStruct(material);
  
  // This yields the empty learner
  Pair<Guesser, Double> p = bestLearner(material, 
    ll(new GWordAfterSubject),
    50, 3, true);
    
  // Now we train it with all data for in-program use
  if (p.a != null) p.a.learn(material);
  
  // Print and store
  print("Best learner: " + formatDouble(p.b, 1) + "% - " + struct(p.a));
  best = p.a;
  bestScore = p.b;
}

sbool printDetails, printSuccesses;

static double checkGuesser(L<Example> testMaterial, Guesser g) {
  print();
  int score = 0, n = 0;
  for (final Example e : testMaterial) {
    L<IntRange> r = cast pcall(g, "getVerbTokens", e.tok);
    bool ok = eq(r, e.verbs);
    if (ok) ++score;
    ++n;
    if (printDetails || ok && printSuccesses)
      if (ok)
        print("OK " + e);
      else
        print("FAIL " + (r == null ? "-" : map(r, func(IntRange r) { joinWithSpaces(subList(e.tok, r)) })) + " for " + e);
  }
  printScore(shortClassName(g), score, n);
  ret ratioToPercent(score, n);
}

static double checkGuesserAfterRandomizedPartialLearn(L<Example> testMaterial, Guesser g, double percentToLearn, bool hardMode) {
  Pair<L<Example>> p = getRandomPercent2(testMaterial, percentToLearn);
  g.learn(p.a);
  ret checkGuesser(hardMode ? p.b : testMaterial, g);
}

// best learner with randomized x% training material
// returns guesser, percentage solved
// hardMode = only count scores on untrained examples
static Pair<Guesser, Double> bestLearner(final L<Example> material, L<? extends Guesser> guessers, final double percent, int repetitions, final bool hardMode) {
  new Best<Guesser> best;
  for (final Guesser g : guessers)
    best.put(g, repeatAndAdd_double(repetitions, func {
      checkGuesserAfterRandomizedPartialLearn(material, cloneObject(g), percent, hardMode)
    })/repetitions);
  ret best.pair();
}

static L<Example> learningMaterial() {
  L<Example> out = new L;
  for (Sentence s) {
    if (s.verb() == null) continue;
    L<IntRange> r = ai_parseVerbAction(s.verb());
    if (r != null) {
      L<S> tok = nlTok5(s.text);
      IntRange subject = ai_parseSubjectAction(s.subject());
      subject = charRangeToCodeTokens(tok, subject);
      r = charRangeToCodeTokens(tok, r);
      tok = codeTokens(tok);
      out.add(Example(tok, subject, r));
    }
  }
  ret out;
}

// to be called from applications - works on character level
static void callGuesser(Guesser g, S sentence, SS data) {
  L<S> tok = nlTok5(sentence);
  L<IntRange> r = g.getVerbTokens(new Input(codeTokens(tok),
    charRangeToCodeTokens(tok, ai_parseAction(data.get("subject")))));
  if (r == null) ret;
  data.put(key, ai_renderAction(sentence, codeTokenRangeToChars(tok, first/*XX*/(r))));
}

Began life as a copy of #1008680