标题只有ANSI C库可能如何？

Question

有一个非常流行的名为nuklear的库，它都是用ANSI C编写的，完全是头文件。但是，每个转换单元中只能有一个函数定义，而ANSI C没有inline函数，那么如果没有链接器错误，该库如何正常工作？

Answer 1

从第73行开始是关于如何使用此标题的说明：

/// ## Usage
/// This library is self contained in one single header file and can be used either
/// in header only mode or in implementation mode. The header only mode is used
/// by default when included and allows including this header in other headers
/// and does not contain the actual implementation. <br /><br />
///
/// The implementation mode requires to define  the preprocessor macro
/// NK_IMPLEMENTATION in *one* .c/.cpp file before #includeing this file, e.g.:
///
/// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~C
///     #define NK_IMPLEMENTATION
///     #include "nuklear.h"
/// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

所以通常包含这个头文件只会给你声明。如果您在包含之前#define NK_IMPLEMENTATION，则包含实施。