Method operator!=

tests/Issue255.cpp:12–12

    std::size_t m_pos;
    bool        operator==( const Iterator& other ) { return m_iterable == other.m_iterable && m_pos == other.m_pos; }
    bool        operator!=( const Iterator& other ) { return !( this->operator==( other ) ); }
    access_type operator*() {
      Widget tmp = m_iterable->m_storage[m_pos];
      return std::get<access_type>( tmp );