53 lines
1.9 KiB
C++
53 lines
1.9 KiB
C++
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// fig20_05.cpp
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// Demonstrating operators .* and ->*.
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#include <iostream>
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// class Test definition
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class Test {
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public:
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Test(int x) : value{x} {};
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void testFunction() {
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std::cout << "testFunction called\n";
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}
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int value; // public data member
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};
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void arrowStar(Test* ptr); // prototype
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void dotStar(Test* ptr); // prototype
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int main() {
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Test test{8};
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arrowStar(&test); // pass address to arrowStar
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dotStar(&test); // pass address to dotStar
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}
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// access member function of Test object using ->*
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void arrowStar(Test* ptr) {
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auto functionPtr{&Test::testFunction}; // pointer to a member function
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(ptr->*functionPtr)(); // invoke function indirectly
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}
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// access members of Test object data member using .*
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void dotStar(Test* ptr) {
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auto valuePtr{&Test::value}; // pointer to a data member
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std::cout << "value is " << (*ptr).*valuePtr << "\n"; // access value
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}
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/**************************************************************************
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* (C) Copyright 1992-2022 by Deitel & Associates, Inc. and *
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* Pearson Education, Inc. All Rights Reserved. *
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* *
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* DISCLAIMER: The authors and publisher of this book have used their *
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* best efforts in preparing the book. These efforts include the *
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* development, research, and testing of the theories and programs *
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* to determine their effectiveness. The authors and publisher make *
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* no warranty of any kind, expressed or implied, with regard to these *
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* programs or to the documentation contained in these books. The authors *
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* and publisher shall not be liable in any event for incidental or *
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* consequential damages in connection with, or arising out of, the *
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* furnishing, performance, or use of these programs. *
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**************************************************************************/
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