### Question:
Facts implements Iterable<Fact<?>> { public void clear() { facts.clear(); }  void put(String name, T value); void add(Fact<T> fact); void remove(String factName); void remove(Fact<T> fact); @SuppressWarnings("unchecked") T get(String factName); Fact<?> getFact(String factName); Map<String, Object> asMap(); @Override Iterator<Fact<?>> iterator(); void clear(); @Override String toString();  }### Answer:
@Test public void testClear() { Facts facts = new Facts(); facts.add(new Fact<>("foo", 1)); facts.clear(); assertThat(facts).isEmpty(); }