sol2/include/sol/stack_check_get_qualified.hpp

// sol3

// The MIT License (MIT)

// Copyright (c) 2013-2019 Rapptz, ThePhD and contributors

// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
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#ifndef SOL_STACK_CHECK_QUALIFIED_GET_HPP
#define SOL_STACK_CHECK_QUALIFIED_GET_HPP

#include "stack_core.hpp"
#include "stack_check_get_unqualified.hpp"
#include "optional.hpp"

namespace sol { namespace stack {
	template <typename T, typename C>
	struct qualified_check_getter {
		typedef decltype(stack_detail::unchecked_get<T>(nullptr, -1, std::declval<record&>())) R;

		template <typename Handler>
		static optional<R> get(lua_State* L, int index, Handler&& handler, record& tracking) {
			if constexpr (is_lua_reference_v<T>) {
				// actually check if it's none here, otherwise
				// we'll have a none object inside an optional!
				bool success = lua_isnoneornil(L, index) == 0 && stack::check<T>(L, index, no_panic);
				if (!success) {
					// expected type, actual type
					tracking.use(static_cast<int>(success));
					handler(L, index, type::poly, type_of(L, index), "");
					return nullopt;
				}
				return stack_detail::unchecked_get<T>(L, index, tracking);
			}
			else {
				if (!check<T>(L, index, std::forward<Handler>(handler))) {
					tracking.use(static_cast<int>(!lua_isnone(L, index)));
					return nullopt;
				}
				return stack_detail::unchecked_get<T>(L, index, tracking);
			}
		}
	};

	template <typename T>
	struct qualified_getter<T, std::enable_if_t<meta::is_optional_v<T>>> {
		static T get(lua_State* L, int index, record& tracking) {
			using ValueType = typename meta::unqualified_t<T>::value_type;
			if constexpr (is_lua_reference_v<ValueType>) {
				// actually check if it's none here, otherwise
				// we'll have a none object inside an optional!
				bool success = lua_isnoneornil(L, index) == 0 && stack::check<ValueType>(L, index, no_panic);
				if (!success) {
					// expected type, actual type
					tracking.use(static_cast<int>(success));
					return {};
				}
				return stack_detail::unchecked_get<ValueType>(L, index, tracking);
			}
			else {
				if (!check<ValueType>(L, index, &no_panic)) {
					tracking.use(static_cast<int>(!lua_isnone(L, index)));
					return {};
				}
				return stack_detail::unchecked_get<ValueType>(L, index, tracking);
			}
		}
	};

}} // namespace sol::stack

#endif // SOL_STACK_CHECK_QUALIFIED_GET_HPP