C++ keyword: long - cppreference.com (original) (raw)

#include #include #include #include #include   static_assert( sizeof(long) >= 32 / CHAR_BIT && sizeof(unsigned long) >= 32 / CHAR_BIT && std::numeric_limits::min() <= -2'147'483'647l - 1 && //' std::numeric_limits::max() >= 2'147'483'647l && //' std::numeric_limits::max() >= 4'294'967'295ul); //'   // 'long long' and 'unsigned long long' are available since C++11 static_assert( sizeof(long long) >= 64 / CHAR_BIT && sizeof(unsigned long long) >= 64 / CHAR_BIT && std::numeric_limits::min() <= -9'223'372'036'854'775'807ll - 1 && std::numeric_limits::max() >= 9'223'372'036'854'775'807ll && std::numeric_limits::max() >= 18'446'744'073'709'551'615ull);   // concepts are available since C++20 static_assert( std::integral && std::integral && std::integral && std::integral && std::floating_point); // Note that 'long' cannot modify 'float'   static_assert( std::same_as<decltype(0l), signed long int> && std::same_as<decltype(0ll), signed long long int> && std::same_as<decltype(0ul), unsigned long int> && std::same_as<decltype(0ull), unsigned long long int> && std::same_as<decltype(0.l), long double>);   template <typename T, typename... Ts> concept all_same = (... and std::same_as <T, Ts>);   static_assert( all_same<long, long int, signed long, signed long int> && all_same<unsigned long, unsigned long int> && all_same<long long, long long int, signed long long, signed long long int> && all_same<unsigned long long, unsigned long long int>);   #define OUT(...) std::cout << #__VA_ARGS__ << " = " << __VA_ARGS__ << '\n'   int main() { std::cout.imbue(std::locale("en_US.UTF-8"));   OUT(sizeof(long)); OUT(std::numeric_limits::min()); OUT(std::numeric_limits::max()); OUT(std::numeric_limits::max());   OUT(sizeof(long long)); OUT(std::numeric_limits::min()); OUT(std::numeric_limits::max()); OUT(std::numeric_limits::max()); }   #undef OUT

sizeof(long) = 8 std::numeric_limits::min() = -9,223,372,036,854,775,808 std::numeric_limits::max() = 9,223,372,036,854,775,807 std::numeric_limits::max() = 18,446,744,073,709,551,615 sizeof(long long) = 8 std::numeric_limits::min() = -9,223,372,036,854,775,808 std::numeric_limits::max() = 9,223,372,036,854,775,807 std::numeric_limits::max() = 18,446,744,073,709,551,615