typeconversionfanout.cpp

ThinkingC++中文版

//: C12:TypeConversionFanout.cpp
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 2000
// Copyright notice in Copyright.txt
class Orange {};
class Pear {};

class Apple {
public:
  operator Orange() const;//convert an apple to an orange
  operator Pear() const;  //convert an apple to a pear
};

// Overloaded eat():
void eat(Orange);
void eat(Pear);

void main()
{
  Apple c;
  eat(c);
  // Error: Apple -> Orange or Apple -> Pear ???
} ///:~


/*

class Orange {};
class Pear {};

class Apple {
public:
  Orange Make_Orange() const;
  Pear Make_Pear() const;
};

// Overloaded eat():
void eat(Orange);
void eat(Pear);

void main()
{
  Apple c;
  eat(c.Make_Orange());
  // Error: Apple -> Orange or Apple -> Pear ???
} ///:~

*/