diff options
| author | untodesu <kirill@untode.su> | 2025-03-15 16:22:09 +0500 |
|---|---|---|
| committer | untodesu <kirill@untode.su> | 2025-03-15 16:22:09 +0500 |
| commit | 3bf42c6ff3805a0d42bbc661794a95ff31bedc26 (patch) | |
| tree | 05049955847504808d6bed2bb7b155f8b03807bb /deps/include/entt/core/iterator.hpp | |
| parent | 02294547dcde0d4ad76e229106702261e9f10a51 (diff) | |
| download | voxelius-3bf42c6ff3805a0d42bbc661794a95ff31bedc26.tar.bz2 voxelius-3bf42c6ff3805a0d42bbc661794a95ff31bedc26.zip | |
Add whatever I was working on for the last month
Diffstat (limited to 'deps/include/entt/core/iterator.hpp')
| -rw-r--r-- | deps/include/entt/core/iterator.hpp | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/deps/include/entt/core/iterator.hpp b/deps/include/entt/core/iterator.hpp new file mode 100644 index 0000000..fdb2ee2 --- /dev/null +++ b/deps/include/entt/core/iterator.hpp @@ -0,0 +1,197 @@ +#ifndef ENTT_CORE_ITERATOR_HPP
+#define ENTT_CORE_ITERATOR_HPP
+
+#include <iterator>
+#include <memory>
+#include <type_traits>
+#include <utility>
+
+namespace entt {
+
+/**
+ * @brief Helper type to use as pointer with input iterators.
+ * @tparam Type of wrapped value.
+ */
+template<typename Type>
+struct input_iterator_pointer final {
+ /*! @brief Value type. */
+ using value_type = Type;
+ /*! @brief Pointer type. */
+ using pointer = Type *;
+ /*! @brief Reference type. */
+ using reference = Type &;
+
+ /**
+ * @brief Constructs a proxy object by move.
+ * @param val Value to use to initialize the proxy object.
+ */
+ constexpr input_iterator_pointer(value_type &&val) noexcept(std::is_nothrow_move_constructible_v<value_type>)
+ : value{std::move(val)} {}
+
+ /**
+ * @brief Access operator for accessing wrapped values.
+ * @return A pointer to the wrapped value.
+ */
+ [[nodiscard]] constexpr pointer operator->() noexcept {
+ return std::addressof(value);
+ }
+
+ /**
+ * @brief Dereference operator for accessing wrapped values.
+ * @return A reference to the wrapped value.
+ */
+ [[nodiscard]] constexpr reference operator*() noexcept {
+ return value;
+ }
+
+private:
+ Type value;
+};
+
+/**
+ * @brief Plain iota iterator (waiting for C++20).
+ * @tparam Type Value type.
+ */
+template<typename Type>
+class iota_iterator final {
+ static_assert(std::is_integral_v<Type>, "Not an integral type");
+
+public:
+ /*! @brief Value type, likely an integral one. */
+ using value_type = Type;
+ /*! @brief Invalid pointer type. */
+ using pointer = void;
+ /*! @brief Non-reference type, same as value type. */
+ using reference = value_type;
+ /*! @brief Difference type. */
+ using difference_type = std::ptrdiff_t;
+ /*! @brief Iterator category. */
+ using iterator_category = std::input_iterator_tag;
+
+ /*! @brief Default constructor. */
+ constexpr iota_iterator() noexcept
+ : current{} {}
+
+ /**
+ * @brief Constructs an iota iterator from a given value.
+ * @param init The initial value assigned to the iota iterator.
+ */
+ constexpr iota_iterator(const value_type init) noexcept
+ : current{init} {}
+
+ /**
+ * @brief Pre-increment operator.
+ * @return This iota iterator.
+ */
+ constexpr iota_iterator &operator++() noexcept {
+ return ++current, *this;
+ }
+
+ /**
+ * @brief Post-increment operator.
+ * @return This iota iterator.
+ */
+ constexpr iota_iterator operator++(int) noexcept {
+ iota_iterator orig = *this;
+ return ++(*this), orig;
+ }
+
+ /**
+ * @brief Dereference operator.
+ * @return The underlying value.
+ */
+ [[nodiscard]] constexpr reference operator*() const noexcept {
+ return current;
+ }
+
+private:
+ value_type current;
+};
+
+/**
+ * @brief Comparison operator.
+ * @tparam Type Value type of the iota iterator.
+ * @param lhs A properly initialized iota iterator.
+ * @param rhs A properly initialized iota iterator.
+ * @return True if the two iterators are identical, false otherwise.
+ */
+template<typename Type>
+[[nodiscard]] constexpr bool operator==(const iota_iterator<Type> &lhs, const iota_iterator<Type> &rhs) noexcept {
+ return *lhs == *rhs;
+}
+
+/**
+ * @brief Comparison operator.
+ * @tparam Type Value type of the iota iterator.
+ * @param lhs A properly initialized iota iterator.
+ * @param rhs A properly initialized iota iterator.
+ * @return True if the two iterators differ, false otherwise.
+ */
+template<typename Type>
+[[nodiscard]] constexpr bool operator!=(const iota_iterator<Type> &lhs, const iota_iterator<Type> &rhs) noexcept {
+ return !(lhs == rhs);
+}
+
+/**
+ * @brief Utility class to create an iterable object from a pair of iterators.
+ * @tparam It Type of iterator.
+ * @tparam Sentinel Type of sentinel.
+ */
+template<typename It, typename Sentinel = It>
+struct iterable_adaptor final {
+ /*! @brief Value type. */
+ using value_type = typename std::iterator_traits<It>::value_type;
+ /*! @brief Iterator type. */
+ using iterator = It;
+ /*! @brief Sentinel type. */
+ using sentinel = Sentinel;
+
+ /*! @brief Default constructor. */
+ constexpr iterable_adaptor() noexcept(std::is_nothrow_default_constructible_v<iterator> &&std::is_nothrow_default_constructible_v<sentinel>)
+ : first{},
+ last{} {}
+
+ /**
+ * @brief Creates an iterable object from a pair of iterators.
+ * @param from Begin iterator.
+ * @param to End iterator.
+ */
+ constexpr iterable_adaptor(iterator from, sentinel to) noexcept(std::is_nothrow_move_constructible_v<iterator> &&std::is_nothrow_move_constructible_v<sentinel>)
+ : first{std::move(from)},
+ last{std::move(to)} {}
+
+ /**
+ * @brief Returns an iterator to the beginning.
+ * @return An iterator to the first element of the range.
+ */
+ [[nodiscard]] constexpr iterator begin() const noexcept {
+ return first;
+ }
+
+ /**
+ * @brief Returns an iterator to the end.
+ * @return An iterator to the element following the last element of the
+ * range.
+ */
+ [[nodiscard]] constexpr sentinel end() const noexcept {
+ return last;
+ }
+
+ /*! @copydoc begin */
+ [[nodiscard]] constexpr iterator cbegin() const noexcept {
+ return begin();
+ }
+
+ /*! @copydoc end */
+ [[nodiscard]] constexpr sentinel cend() const noexcept {
+ return end();
+ }
+
+private:
+ It first;
+ Sentinel last;
+};
+
+} // namespace entt
+
+#endif
|