// e. g.
// if (Y -> is the opposite of -> X)
// and input (if something is not X, then it is...)
// then say (Y!)

static S ai_ifAndInput_v2(S rule, S input) {
  print("ai_ifAndInput_v2");
  new Matches m;
  if (!simpleStarMatchOnCTokensIC("if * and input * then say *",
    javaTokDroppingBracketsC_unquote(rule), m)) unsuitableRule();
    
  S d2 = $2;
  printStructs(+d2, +input);
  S x = matchBigX(d2, input);
  printStructs(+x);
  if (x == null) null;
  S pat = formatVars($1, litmap("X", x, "Y", "$X"));
  printStruct(+pat);
  T3<S> t = ai_tripelize(pat);
  printStruct(+t);
  
  S y = random(ai_texts(t));
  if (y == null) null;
  ret ai_replaceBigY($3, y);
}

Began life as a copy of #1013172