As you can see, to check whether na

As you can see, to check whether narrowing applies, even the current values might be considered, if
available at compile time. As Bjarne Stroustrup writes in [Stroustrup:FAQ] regarding this example:
“The way C++11 avoids a lot of incompatibilities is by relying on the actual values of initializers
(such as 7 in the example above) when it can (and not just type) when deciding what is a narrowing
conversion. If a value can be represented exactly as the target type, the conversion is not narrowing.
Note that floating-point to integer conversions are always considered narrowing— even 7.0 to 7.”

Results (English) 3:

正如你所看到的，检查是否缩小适用，即使当前的值可能会认为，如果
在编译时可用。正如Bjarne Stroustrup写[ Stroustrup：常见问题解答】对于这个例子：
”方式的C 11避免许多不依靠的初始化
实际值（如上面例子中的7）时，它可以（不只是型）在决定缩小
是什么转换。如果一个值可以精确表示为目标类型，转换不缩小。
注意浮点到整数的转换总是被缩小到7甚至7。”