code: @Nonnull
      public final <B> ImmutableList<B> bind(@Nonnull F<A, ImmutableList<B>> f) {
          return this.flatMap(f);
      }
docs: A synonym of {@link #flatMap}.
  
  @param f   The function.
  @param <B> The type of result function.
  @return The result of bind.