CHAPTER 10:EX 24

最新推荐文章于 2021-05-27 16:55:18 发布

原创最新推荐文章于 2021-05-27 16:55:18 发布 · 516 阅读

0 ·

CC 4.0 BY-SA版权

THINKING IN C++ 专栏收录该内容

22 篇文章

订阅专栏

#ifndef BOB_H
#define BOB_H
namespace bob{
  class Widget { /* ... */ };
  class Poppit { /* ... */ };
  // ...
}
#endif    //BOB_H

/**//*

24. Extract the namespace declarations in

BobsSuperDuperLibrary.cpp and

UnnamedNamespaces.cpp and put them in separate

header files, giving the unnamed namespace a name in

the process. In a third header file create a new namespace

that combines the elements of the other two namespaces

with using declarations. In main( ), introduce your new

namespace with a using directive and access all the

elements of your namespace.

#ifndef NEW1_H

#define NEW1_H

#include"bob.h"

#include"tom.h"

namespace new1...{

using bob::Widget;

using bob::Poppit;

using tom::Arm;

using tom::Head;

using tom::Leg;

using tom::Robot;

}

#endif //NEW_H

#include "new.h"
int main() {
using namespace new1;
Arm a;
}

#ifndef TOM_H
#define TOM_H
namespace tom{
  class Arm  { /* ... */ };
  class Leg  { /* ... */ };
  class Head { /* ... */ };
  class Robot {
    Arm arm[4];
    Leg leg[16];
    Head head[3];
    // ...
  } xanthan;
  int i, j, k;
}
#endif    //TOM_H