/usr/include/boost/core
NameSizeModeActions
addressof.hpp61530644editdlrm
allocator_access.hpp159440644editdlrm
alloc_construct.hpp34360644editdlrm
checked_delete.hpp16770644editdlrm
default_allocator.hpp33330644editdlrm
demangle.hpp30340644editdlrm
empty_value.hpp33240644editdlrm
enable_if.hpp33150644editdlrm
exchange.hpp9110644editdlrm
explicit_operator_bool.hpp53540644editdlrm
first_scalar.hpp8130644editdlrm
ignore_unused.hpp19760644editdlrm
is_same.hpp7930644editdlrm
lightweight_test.hpp184430644editdlrm
lightweight_test_trait.hpp39730644editdlrm
noinit_adaptor.hpp17910644editdlrm
noncopyable.hpp19110644editdlrm
no_exceptions_support.hpp18720644editdlrm
null_deleter.hpp12320644editdlrm
nvp.hpp10000644editdlrm
pointer_traits.hpp50720644editdlrm
quick_exit.hpp10980644editdlrm
ref.hpp59760644editdlrm
scoped_enum.hpp78800644editdlrm
swap.hpp21230644editdlrm
typeinfo.hpp31510644editdlrm
uncaught_exceptions.hpp68190644editdlrm
underlying_type.hpp22050644editdlrm
use_default.hpp3000644editdlrm
Edit: /usr/include/boost/core/empty_value.hpp (3324B)
/* Copyright 2018 Glen Joseph Fernandes (glenjofe@gmail.com) Distributed under the Boost Software License, Version 1.0. (http://www.boost.org/LICENSE_1_0.txt) */ #ifndef BOOST_CORE_EMPTY_VALUE_HPP #define BOOST_CORE_EMPTY_VALUE_HPP #include #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) #include #endif #if defined(BOOST_GCC_VERSION) && (BOOST_GCC_VERSION >= 40700) #define BOOST_DETAIL_EMPTY_VALUE_BASE #elif defined(BOOST_INTEL) && defined(_MSC_VER) && (_MSC_VER >= 1800) #define BOOST_DETAIL_EMPTY_VALUE_BASE #elif defined(BOOST_MSVC) && (BOOST_MSVC >= 1800) #define BOOST_DETAIL_EMPTY_VALUE_BASE #elif defined(BOOST_CLANG) && !defined(__CUDACC__) #if __has_feature(is_empty) && __has_feature(is_final) #define BOOST_DETAIL_EMPTY_VALUE_BASE #endif #endif namespace boost { template struct use_empty_value_base { enum { #if defined(BOOST_DETAIL_EMPTY_VALUE_BASE) value = __is_empty(T) && !__is_final(T) #else value = false #endif }; }; struct empty_init_t { }; namespace empty_ { template::value> class empty_value { public: typedef T type; #if !defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) empty_value() = default; #else empty_value() { } #endif empty_value(boost::empty_init_t) : value_() { } #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) template empty_value(boost::empty_init_t, U&& value, Args&&... args) : value_(std::forward(value), std::forward(args)...) { } #else template empty_value(boost::empty_init_t, U&& value) : value_(std::forward(value)) { } #endif #else template empty_value(boost::empty_init_t, const U& value) : value_(value) { } template empty_value(boost::empty_init_t, U& value) : value_(value) { } #endif const T& get() const BOOST_NOEXCEPT { return value_; } T& get() BOOST_NOEXCEPT { return value_; } private: T value_; }; #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION) template class empty_value : T { public: typedef T type; #if !defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) empty_value() = default; #else empty_value() { } #endif empty_value(boost::empty_init_t) : T() { } #if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) #if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) template empty_value(boost::empty_init_t, U&& value, Args&&... args) : T(std::forward(value), std::forward(args)...) { } #else template empty_value(boost::empty_init_t, U&& value) : T(std::forward(value)) { } #endif #else template empty_value(boost::empty_init_t, const U& value) : T(value) { } template empty_value(boost::empty_init_t, U& value) : T(value) { } #endif const T& get() const BOOST_NOEXCEPT { return *this; } T& get() BOOST_NOEXCEPT { return *this; } }; #endif } /* empty_ */ using empty_::empty_value; BOOST_INLINE_CONSTEXPR empty_init_t empty_init = empty_init_t(); } /* boost */ #endif