fig22_12.cpp

来自「《c＋＋大学教程》源码」· C++ 代码 · 共 46 行

// Fig. 21.12: fig21_12.cpp
// Demonstrating storage class specifier mutable.
#include <iostream>

using std::cout;
using std::endl;

// class TestMutable definition
class TestMutable {
public:
   TestMutable( int v = 0 ) { value = v; }
   void modifyValue() const { value++; }
   int getValue() const { return value; }
private:
   mutable int value;  // mutable member

};  // end class TestMutable

int main()
{
   const TestMutable test( 99 );
   
   cout << "Initial value: " << test.getValue();

   test.modifyValue();   // modifies mutable member
   cout << "\nModified value: " << test.getValue() << endl;

   return 0;

}  // end main

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