// The idea is to postprocess to match out

// e.g. out="a, b, c"

// and f=FJoin(", ")

static class LPost extends LearnerImpl {

  ReversibleFunction f;

  Learner base;

  *(ReversibleFunction *f, Learner *base) {}

  public void processInOut(Object in, Object out) {

    out = f.unprocess(out);

    base.processInOut(in, out);

  }

  public Object processIn(Object in) {

    in = base.processIn(in);

    in = f.process(in);

    return in;

  }

  public void toJava(Code code) {

    base.toJava(code);

    f.toJava_process(code);

  }

}