disjunction.hpp

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// Copyright 2026, Toyota Motor Corporation
//
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
#ifndef INCLUDE_GUARD_ARENE_BASE_ARENE_BASE_TYPE_TRAITS_DISJUNCTION_HPP_
#define INCLUDE_GUARD_ARENE_BASE_ARENE_BASE_TYPE_TRAITS_DISJUNCTION_HPP_
 
// IWYU pragma: private, include "arene/base/type_traits.hpp"
// IWYU pragma: friend "(arene/base(?!/tests)|stdlib/include/stdlib_detail)/.*"
 
#include "arene/base/stdlib_choice/integral_constant.hpp"
#include "arene/base/type_traits/conditional.hpp"
 
namespace arene {
namespace base {
 
// parasoft-begin-suppress AUTOSAR-A2_7_3-a "False positive: all declarations are documented."
/// @brief Combines the values of multiple boolean type traits with a logical OR operation
/// @tparam BoolTraits the traits to combine
/// @note Evaluation short circuits: If @c bool(BoolTrait[N]::value) is @c true , then the remaining @c
/// BoolTraits::value... are not evaluated. The resulting type inherits from either the first @c BoolTraits[N] whose
/// value is @c true , or the final type in @c BoolTraits... if no such trait exists. If @c BoolTraits... is empty,
/// then the type is @c std::false_type .
template <typename...>
class disjunction : public std::false_type {};
 
/// @brief Specialization of @c arene::base::disjunction for a single trait. The result is that trait.
/// @tparam BoolTrait The trait to evaluate
template <typename BoolTrait>
class disjunction<BoolTrait> : public BoolTrait {};
 
/// @brief Specialization of @c arene::base::disjunction for multiple traits.
/// @tparam BoolTrait The first trait to evaluate
/// @tparam Rest The remaining traits to evaluate
template <typename BoolTrait, typename... Rest>
class disjunction<BoolTrait, Rest...>
    : public conditional_t<bool(BoolTrait::value), BoolTrait, disjunction<Rest...>> {};
 
/// @brief The combined value of multiple boolean type traits through a logical OR operation.
/// @tparam BoolTraits the traits to combine
/// @returns bool Equivalent to <c> BoolTraits::value || ... </c> .
/// @note Evaluation short circuits: If @c BoolTrait[N]::value is @c true , then the remaining @c BoolTraits::value...
/// are not evaluated.
template <typename... BoolTraits>
extern constexpr bool disjunction_v{disjunction<BoolTraits...>::value};
// parasoft-end-suppress AUTOSAR-A2_7_3-a "False positive: all declarations are documented."
 
}  // namespace base
}  // namespace arene
 
#endif  // INCLUDE_GUARD_ARENE_BASE_ARENE_BASE_TYPE_TRAITS_DISJUNCTION_HPP_