forked from OctaForge/libostd
simplify range-for-only iterators using relaxed c++17 rules
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@ -1121,7 +1121,9 @@ public:
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/** Implements a minimal iterator just for range-based for loop.
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* Do not use directly.
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*/
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detail::generator_iterator<T> end() noexcept;
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std::nullptr_t end() noexcept {
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return nullptr;
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}
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/** Swaps two generators' states. */
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void swap(generator &other) noexcept {
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@ -1239,7 +1241,9 @@ struct generator_range: input_range<generator_range<T>> {
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/** Implements a minimal iterator just for range-based for loop.
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* Do not use directly.
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*/
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detail::generator_iterator<T> end() noexcept;
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std::nullptr_t end() noexcept {
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return nullptr;
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}
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private:
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generator<T> *p_gen;
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@ -1257,7 +1261,7 @@ namespace detail {
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generator_iterator() = delete;
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generator_iterator(generator<T> &g): p_gen(&g) {}
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bool operator!=(generator_iterator const &) noexcept {
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bool operator!=(std::nullptr_t) noexcept {
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return !p_gen->empty();
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}
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@ -1280,21 +1284,11 @@ detail::generator_iterator<T> generator<T>::begin() noexcept {
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return detail::generator_iterator<T>{*this};
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}
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template<typename T>
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detail::generator_iterator<T> generator<T>::end() noexcept {
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return detail::generator_iterator<T>{*this};
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}
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template<typename T>
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detail::generator_iterator<T> generator_range<T>::begin() noexcept {
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return detail::generator_iterator<T>{*p_gen};
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}
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template<typename T>
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detail::generator_iterator<T> generator_range<T>::end() noexcept {
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return detail::generator_iterator<T>{*p_gen};
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}
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/** @} */
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} /* namespace ostd */
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@ -230,55 +230,23 @@ constexpr bool is_output_range = detail::is_output_range_base<T>;
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namespace detail {
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// range iterator
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template<typename T>
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struct range_iterator {
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range_iterator(): p_range(), p_init(false) {}
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explicit range_iterator(T const &range): p_range(), p_init(true) {
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::new(&get_ref()) T(range);
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}
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explicit range_iterator(T &&range): p_range(), p_init(true) {
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::new(&get_ref()) T(std::move(range));
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}
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range_iterator(const range_iterator &v): p_range(), p_init(true) {
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::new(&get_ref()) T(v.get_ref());
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}
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range_iterator(range_iterator &&v): p_range(), p_init(true) {
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::new(&get_ref()) T(std::move(v.get_ref()));
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}
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range_iterator &operator=(const range_iterator &v) {
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destroy();
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::new(&get_ref()) T(v.get_ref());
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p_init = true;
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return *this;
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}
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range_iterator &operator=(range_iterator &&v) {
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destroy();
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swap(v);
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return *this;
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}
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~range_iterator() {
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destroy();
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}
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range_iterator() = delete;
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explicit range_iterator(T const &range): p_range(range) {}
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explicit range_iterator(T &&range): p_range(std::move(range)) {}
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range_iterator &operator++() {
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get_ref().pop_front();
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p_range.pop_front();
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return *this;
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}
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range_reference_t<T> operator*() const {
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return get_ref().front();
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return p_range.front();
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}
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bool operator!=(std::nullptr_t) const {
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return !p_range.empty();
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}
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bool operator!=(range_iterator) const { return !get_ref().empty(); }
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private:
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T &get_ref() { return *reinterpret_cast<T *>(&p_range); }
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T const &get_ref() const { return *reinterpret_cast<T const *>(&p_range); }
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void destroy() {
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if (p_init) {
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get_ref().~T();
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p_init = false;
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}
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}
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std::aligned_storage_t<sizeof(T), alignof(T)> p_range;
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bool p_init;
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std::decay_t<T> p_range;
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};
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}
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@ -553,8 +521,8 @@ struct input_range {
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detail::range_iterator<B> begin() const {
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return detail::range_iterator<B>(*static_cast<B const *>(this));
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}
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detail::range_iterator<B> end() const {
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return detail::range_iterator<B>();
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std::nullptr_t end() const {
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return nullptr;
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}
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template<typename Size>
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