作为一个认为他们已经对C复杂性有了基本了解的人,这个项目无疑已经证明是一种令人羞愧的经历.如果有人能够看到他们的方式来启发我在这里发生了什么,我会永远感激.与此同时,我将不得不拔出C书,以便在我所知道的和我认为知道的东西之间调和.

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

// Class for holding a reference to type char,retuned by the "operator[](int)"
// method of class "TestString". Independent methods permit differentiation
// between lvalue and rvalue contexts.
class CReference
{
 private:
   char& m_characterReference;

 public:
   // Construct CReference from char&
   CReference(char& m_initialiser)
     : m_characterReference(m_initialiser) {}

   // Invoked when object is referenced in a rvalue char context.
   operator char()
   {
    return m_characterReference;
   }

   // Invoked when object is referenced in a lvalue char= context.
   char operator=(char c)
   {
    m_characterReference = c;
    return c;
   }

   // NEVER INVOKED,but will not compile without! WHY???
   void operator=(CReference &p_assignator){}
};


// Simple string class which permits the manipulation of single characters
// via its "operator[](int)" method.
class TestString
{
 private:
   char m_content[23];

 public:
   // Construct string with test content.
   TestString()
   {
    strcpy(m_content,"This is a test object.");
   }

   // Return pointer to content.
   operator const char*()
   {
    m_content[22] = 0;
    return m_content;
   }

   // Return reference to indexed character.
   CReference operator[](int index)
   {
    return m_content[index];
   }
};


int main(int argc,char *argv[])
{
 TestString s1;

 // Test both lvalue and rvalue subscript access.
 s1[0] = s1[1]; 

 // Print test string.
 printf("%s\n",(const char*)s1);
 return 0;
}