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C++ keyword: return

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用法

  • return 语句:作为该语句的声明

示例

#include <cstdlib>
#include <iostream>
[[nodiscard]] constexpr auto clamp(int value, int min, int max) noexcept
{
    if (value <= min)
        return min;
    else if (max <= value)
        return max;
    return value;
    // 不会在 'return' 语句之后执行
    std::exit(value);
}
int main() noexcept
{
    std::cout << clamp(1, 2, 4);
    std::cout << clamp(3, 2, 4);
    std::cout << clamp(5, 2, 4);
    return 0; // main() 中的值 '0' 表示执行成功
}

输出:

234

参见

(自 C++17 起)
(自 C++23 起)
(自 C++20 起)