}
        return interner;
      }
    },
    StrongInternerImpl {
      @Override
      public <E> Interner<E> create(Collection<E> contents) {
        Interner<E> interner = Interners.newStrongInterner();
        for (E e : contents) {
          E unused = interner.intern(e);
        }
        return interner;
      }
    };
  }

  public enum Value {
    INSTANCE;
  }