向控制台打印时间函数产生 1
Printing time function to console produces 1
几个开发人员和我想知道为什么：
std::cout<<std::time<<std::endl;
打印出值为 1。该值代表什么，为什么值为 1。
对发生的事情的回答：
How to print function pointers with cout?
C++ 标准规定：
4.12 Boolean conversions
1 An rvalue of arithmetic, enumeration, pointer, or pointer to member
type can be converted to an rvalue of type bool.
引自匿名：
This is the only conversion specified for function pointers.
编辑：下面的答案很好地展示了为什么打印 1 而不是任何布尔值的解决方案，并解释了 1 何时不会出现。
cppreference 说：
There are no overload for pointers to non-static member, pointers to
volatile, or function pointers (other than the ones with signatures
accepted by the (10-12) overloads). Attempting to output such objects
invokes implicit conversion to bool, and, for any non-null pointer
value, the value 1 is printed (unless boolalpha was set, in which case
true is printed).
所以你得到函数指针 std::time 转换为 bool 并且它总是 true 没有 boolalpha 将输出设置为 1.
几个开发人员和我想知道为什么：
std::cout<<std::time<<std::endl;
打印出值为 1。该值代表什么，为什么值为 1。
对发生的事情的回答： How to print function pointers with cout?
C++ 标准规定：
4.12 Boolean conversions
1 An rvalue of arithmetic, enumeration, pointer, or pointer to member type can be converted to an rvalue of type bool.
引自匿名：
This is the only conversion specified for function pointers.
编辑：下面的答案很好地展示了为什么打印 1 而不是任何布尔值的解决方案，并解释了 1 何时不会出现。
cppreference 说：
There are no overload for pointers to non-static member, pointers to volatile, or function pointers (other than the ones with signatures accepted by the (10-12) overloads). Attempting to output such objects invokes implicit conversion to bool, and, for any non-null pointer value, the value 1 is printed (unless boolalpha was set, in which case true is printed).
所以你得到函数指针 std::time 转换为 bool 并且它总是 true 没有 boolalpha 将输出设置为 1.