// https://www.sololearn.com/Discuss/1657370/how-to-create-own-data-types-in-cpp #include #include #include #include #include template class List { public: // default constructor List() noexcept : m_size{0} , m_list{nullptr} {} // parametrized constructor List(std::initializer_list list) noexcept : m_size{ std::size(list) } { if ( auto buffer = std::aligned_alloc(alignof(T), sizeof(T) * std::size(list)) ) { m_list = static_cast(buffer); std::uninitialized_copy(std::begin(list), std::end(list), m_list); } } // copy constructor List(List const& list) noexcept : m_size{ std::size(list) } { if ( auto buffer = std::aligned_alloc(alignof(T), sizeof(T) * std::size(list)) ) { m_list = static_cast(buffer); std::uninitialized_copy(std::begin(list), std::end(list), m_list); } } // move constructor List(List&& list) noexcept : List{} { swap(list, *this); } // copy assignment (copy swap idiom) auto operator=(List list) noexcept -> List & { swap(list, *this); return *this; } public: friend void swap(List& lhs, List& rhs) noexcept { using std::swap; swap(lhs.m_size, rhs.m_size); swap(lhs.m_list, rhs.m_list); } // subscript operator overloading auto operator[](int indx) noexcept -> T& { return m_list[indx]; } auto operator[](int indx) const noexcept -> T& { return m_list[indx]; } // define begin to support the range-for loop for our List auto begin() noexcept -> T* { return m_list; } auto begin() const noexcept -> T const* { return m_list; } // define end to support the range-for loop for our List auto end() noexcept -> T* { return (m_list + m_size); } auto end() const noexcept -> T const* { return (m_list + m_size); } // destructor ~List() noexcept { std::destroy( m_list, m_list + m_size); std::free( static_cast(m_list) ); m_size = 0UL; m_list = nullptr; } private: std::size_t m_size; T* m_list; }; template std::ostream& operator<<(std::ostream& out, List const& list) noexcept { std::copy( std::begin(list), std::end(list), std::ostream_iterator(out, " ")); return out << std::endl; } int main(void) { List list {10,20,30,40,50,60,70,80,90}; // simple output std::cout << "list: " << list << std::endl; return 0; }

List type