1. 程式人生 > >VS2015--win32工程配置的一些想法之Google Code Style中標頭檔案的順序

VS2015--win32工程配置的一些想法之Google Code Style中標頭檔案的順序

工程大了,有很多的標頭檔案,也要引用很多的庫檔案。
從我們學習C++寫hello world的那一刻起,就知道要包含一些系統檔案。

那麼順序如何呢?
在review的時候,感覺自己寫的東西就是一坨屎。

看看Google code style中是如何描述include檔案順序的:

Names and Order of Includes
Use standard order for readability and to avoid hidden dependencies: C library, C++ library, other libraries’ .h, your project’s .h.

All of a project’s header files should be listed as descendants of the project’s source directory without use of UNIX directory shortcuts . (the current directory) or .. (the parent directory). For example, google-awesome-project/src/base/logging.h should be included as

#include "base/logging.h"

In dir/foo.cc or dir/foo_test.cc, whose main purpose is to implement or test the stuff in dir2/foo2.h, order your includes as follows:

dir2/foo2.h (preferred location — see details below).
C system files.
C++ system files.
Other libraries’ .h files.
Your project’s .h files.

The preferred ordering reduces hidden dependencies. We want every header file to be compilable on its own. The easiest way to achieve this is to make sure that every one of them is the first .h file #included in some .cc.

dir/foo.cc and dir2/foo2.h are often in the same directory (e.g. base/basictypes_test.cc and base/basictypes.h), but can be in different directories too.

Within each section it is nice to order the includes alphabetically.

For example, the includes in google-awesome-project/src/foo/internal/fooserver.cc might look like this:

#include "foo/public/fooserver.h"  // Preferred location.

#include <sys/types.h>
#include <unistd.h>

#include <hash_map>
#include <vector>

#include "base/basictypes.h"
#include "base/commandlineflags.h"
#include "foo/public/bar.h"

這用通俗的講,你寫了一個a.h和a.cc,而在.cc檔案中需要用到一些通用的東西位於base資料夾下的base.h中。那麼在a.cc檔案中,你就應該這樣的順序包含:

#include a.h

#include <sys/types.h> 

#include <algorithm>

#include "base/base.h"