public final class Functions {
  private Functions() {}

  /**
   * A function equivalent to the method reference {@code Object::toString}, for users not yet using
   * Java 8. The function simply invokes {@code toString} on its argument and returns the result. It
   * throws a {@link NullPointerException} on null input.
   *
   * <p><b>Warning:</b> The returned function may not be <i>consistent with equals</i> (as

public final class Functions {
  private Functions() {}

  /**
   * A function equivalent to the method reference {@code Object::toString}, for users not yet using
   * Java 8. The function simply invokes {@code toString} on its argument and returns the result. It
   * throws a {@link NullPointerException} on null input.
   *
   * <p><b>Warning:</b> The returned function may not be <i>consistent with equals</i> (as