67 lines
3.0 KiB
C++
67 lines
3.0 KiB
C++
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// fig10_10.cpp
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// Introducing polymorphism, virtual functions and dynamic binding.
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#include <fmt/format.h>
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#include <iostream>
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#include "SalariedEmployee.h"
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#include "SalariedCommissionEmployee.h"
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int main() {
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// create base-class object
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SalariedEmployee salaried{"Sue Jones", 500.0};
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// create derived-class object
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SalariedCommissionEmployee salariedCommission{
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"Bob Lewis", 300.0, 5000.0, .04};
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// output objects using static binding
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std::cout << fmt::format("{}\n{}:\n{}\n{}\n",
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"INVOKING TOSTRING FUNCTION ON BASE-CLASS AND",
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"DERIVED-CLASS OBJECTS WITH STATIC BINDING",
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salaried.toString(), // static binding
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salariedCommission.toString()); // static binding
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std::cout << "INVOKING TOSTRING FUNCTION ON BASE-CLASS AND\n"
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<< "DERIVED-CLASS OBJECTS WITH DYNAMIC BINDING\n\n";
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// natural: aim base-class pointer at base-class object
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SalariedEmployee* salariedPtr{&salaried};
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std::cout << fmt::format("{}\n{}:\n{}\n",
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"CALLING VIRTUAL FUNCTION TOSTRING WITH BASE-CLASS POINTER",
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"TO BASE-CLASS OBJECT INVOKES BASE-CLASS FUNCTIONALITY",
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salariedPtr->toString()); // base-class version
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// natural: aim derived-class pointer at derived-class object
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SalariedCommissionEmployee* salariedCommissionPtr{&salariedCommission};
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std::cout << fmt::format("{}\n{}:\n{}\n",
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"CALLING VIRTUAL FUNCTION TOSTRING WITH DERIVED-CLASS POINTER",
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"TO DERIVED-CLASS OBJECT INVOKES DERIVED-CLASS FUNCTIONALITY",
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salariedCommissionPtr->toString()); // derived-class version
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// aim base-class pointer at derived-class object
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salariedPtr = &salariedCommission;
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// runtime polymorphism: invokes SalariedCommissionEmployee
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// via base-class pointer to derived-class object
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std::cout << fmt::format("{}\n{}:\n{}\n",
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"CALLING VIRTUAL FUNCTION TOSTRING WITH BASE-CLASS POINTER",
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"TO DERIVED-CLASS OBJECT INVOKES DERIVED-CLASS FUNCTIONALITY",
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salariedPtr->toString()); // derived-class version
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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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