#define命名空间中的语句 [英] #define statements within a namespace

问题描述

如果我在这样的名称空间中有一个#define语句:

If I have a #define statement within a namespace as such:

namespace MyNamespace
{
  #define SOME_VALUE 0xDEADBABE
}

我是否正确地说#define语句不限于名称空间?

Am I correct in saying that the #define statement is not restricted to the namespace?

以下是正确"的事情吗?

Is the following the "correct" thing to do?

namespace MyNamespace
{
  const unsigned int SOME_VALUE = 0xDEADBABE;
}

推荐答案

正确，#define不受名称空间的约束. #define是预处理器指令-它导致在通过编译之前对源文件进行操作编译器.在编译步骤中使用了命名空间，并且编译器无法深入了解#define.

Correct,#define's aren't bound by namespaces. #define is a preprocessor directive - it results in manipulation of the source file prior to being compiled via the compiler. Namespaces are used during the compilation step and the compiler has no insight into the #define's.

您应尽量避免使用预处理器.对于像这样的常量值，最好使用const而不是#define.

You should try to avoid the preprocessor as much as possible. For constant values like this, prefer const over #define's.

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