std:: saturate_cast

Converts the value x to a value of type T , clamping x between the minimum and maximum values of type T .

The program is ill-formed if either T or U is not a signed or unsigned integer type (including standard integer type and extended integer type ).

Parameters

Return value

• x , if x is representable as a value of type T . Otherwise,
• either the largest or smallest representable value of type T , whichever is closer to the value of x .

Notes

Possible implementation

See libstdc++ (GCC) .

Example

#include <cstdint>
#include <limits>
#include <numeric>
 
int main()
{
    constexpr std::int16_t x1{696};
 
    constexpr std::int8_t x2 = std::saturate_cast<std::int8_t>(x1);
    static_assert(x2 == std::numeric_limits<std::int8_t>::max());
 
    constexpr std::uint8_t x3 = std::saturate_cast<std::uint8_t>(x1);
    static_assert(x3 == std::numeric_limits<std::uint8_t>::max());
 
    constexpr std::int16_t y1{-696};
 
    constexpr std::int8_t y2 = std::saturate_cast<std::int8_t>(y1);
    static_assert(y2 == std::numeric_limits<std::int8_t>::min());
 
    constexpr std::uint8_t y3 = std::saturate_cast<std::uint8_t>(y1);
    static_assert(y3 == 0);
}

See also