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#define vs. const declaration
原标题:Priority of #define vs. const declaration

a code < < 还是会导致汇编错误?

//ONE
#define FOO 23
const int FOO = 42;

//TWO
const int FOO = 42;
#define FOO 23

联络处在这两种情况下都有哪些价值,即42或23个?

最佳回答

第一,汇编错误。 澳门从其定义的角度来看是显而易见的。

这首先相当于:

//ONE
#define FOO 23
const int 23= 42; //which would cause compilation error

第二是:

//TWO
const int FOO = 42;
#define FOO 23 //if you use FOO AFTER this line, it will be replaced by 23

由于宏观是司空的,在C++const enum中,优于宏观。 参看我在这里所作的回答,其中我解释了为什么宏观是坏的,constenum是更好的选择。

问题回答

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