LiteLoaderBDS-1.16.40/LiteLoader/Header/third-party/entt/meta/range.hpp
2022-09-21 19:47:03 +08:00

101 lines
2.4 KiB
C++

#ifndef ENTT_META_RANGE_HPP
#define ENTT_META_RANGE_HPP
#include <cstddef>
#include <iterator>
namespace entt {
/**
* @brief Iterable range to use to iterate all types of meta objects.
* @tparam Type Type of meta objects returned.
* @tparam Node Type of meta nodes iterated.
*/
template<typename Type, typename Node = typename Type::node_type>
class meta_range {
struct range_iterator {
using difference_type = std::ptrdiff_t;
using value_type = Type;
using pointer = void;
using reference = value_type;
using iterator_category = std::input_iterator_tag;
using node_type = Node;
range_iterator() ENTT_NOEXCEPT = default;
range_iterator(node_type *head) ENTT_NOEXCEPT
: it{head}
{}
range_iterator & operator++() ENTT_NOEXCEPT {
return (it = it->next), *this;
}
range_iterator operator++(int) ENTT_NOEXCEPT {
range_iterator orig = *this;
return ++(*this), orig;
}
[[nodiscard]] reference operator*() const ENTT_NOEXCEPT {
return it;
}
[[nodiscard]] bool operator==(const range_iterator &other) const ENTT_NOEXCEPT {
return other.it == it;
}
[[nodiscard]] bool operator!=(const range_iterator &other) const ENTT_NOEXCEPT {
return !(*this == other);
}
private:
node_type *it{};
};
public:
/*! @brief Node type. */
using node_type = Node;
/*! @brief Input iterator type. */
using iterator = range_iterator;
/*! @brief Default constructor. */
meta_range() ENTT_NOEXCEPT = default;
/**
* @brief Constructs a meta range from a given node.
* @param head The underlying node with which to construct the range.
*/
meta_range(node_type *head)
: node{head}
{}
/**
* @brief Returns an iterator to the beginning.
* @return An iterator to the first meta object of the range.
*/
[[nodiscard]] iterator begin() const ENTT_NOEXCEPT {
return iterator{node};
}
/**
* @brief Returns an iterator to the end.
* @return An iterator to the element following the last meta object of the
* range.
*/
[[nodiscard]] iterator end() const ENTT_NOEXCEPT {
return iterator{};
}
private:
node_type *node{nullptr};
};
}
#endif