52 lines
2.0 KiB
C++
52 lines
2.0 KiB
C++
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// fig09_29.cpp
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// Using the this pointer to refer to object members.
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#include <fmt/format.h>
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#include <iostream>
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class Test {
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public:
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explicit Test(int value);
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void print() const;
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private:
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int m_x{0};
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};
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// constructor
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Test::Test(int value) : m_x{value} {} // initialize x to value
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// print x using implicit then explicit this pointers;
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// the parentheses around *this are required due to precedence
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void Test::print() const {
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// implicitly use the this pointer to access the member x
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std::cout << fmt::format(" m_x = {}\n", m_x);
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// explicitly use the this pointer and the arrow operator
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// to access the member x
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std::cout << fmt::format(" this->m_x = {}\n", this->m_x);
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// explicitly use the dereferenced this pointer and
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// the dot operator to access the member x
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std::cout << fmt::format("(*this).m_x = {}\n", (*this).m_x);
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}
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int main() {
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const Test testObject{12}; // instantiate and initialize testObject
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testObject.print();
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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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