＃定义变量类型 [英] Type of #define variables

问题描述

如果我有：

#define MAXLINE    5000

是什么类型MAXLINE理解为？我应该假设它是一个 INT ？我能以某种方式测试它？

What type is MAXLINE understood to be? Should I assume it is an int? Can I test it somehow?

在一般情况下，一个人如何能确定的#define 编辑变量的类型？

In general, how can one determine the type of #defineed variable?

推荐答案

它没有类型。这是一个简单的文本替换。该文本将5000到位的地方MAXLINE显示为令牌被丢弃。

It has no type. It is a simple text substitution. The text 5000 will be dropped in place wherever MAXLINE appears as a token.

例如：

int a = MAXLINE;

将投入价值5000 A 。

在

char *MAXLINE2 = "MAXLINE";

不会导致

char *50002 = "5000";

所以，如果你想类型检查，宏的不是要走的路。您将要声明静态常量来代替，这样的类型检查是由编译器完成。

So, if you want type-checking, macro's are not the way to go. You will want to declare static constants instead, that way type-checking is done by the compiler.

有关的静态，常量和的#define ，有很多来源，包括这样的问题：静态，定义和常量用C

For information on the differences between static, const, and #define, there are many sources, including this question: static, define, and const in C

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