Embedded Programming with Modern C++/

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- Examples

- Examples

Some examples of copy and move semantics will be discussed in this lesson.

We'll cover the following...

Example 1

C++
// copyMoveSemantic.cpp
#include <iostream>
#include <string>
#include <utility>
int main(){
  std::string str1{"ABCDEF"};
  std::string str2;
  std::cout << "\n";
  // initial value
  std::cout << "str1= " << str1 << std::endl;
  std::cout << "str2= " << str2 << std::endl;
  // copy semantic
  str2= str1;
  std::cout << "str2= str1;\n";
  std::cout << "str1= " << str1 << std::endl;
  std::cout << "str2= " << str2 << std::endl;
  std::cout << "\n";
  std::string str3;
  // initial value
  std::cout << "str1= " << str1 << std::endl;
  std::cout << "str3= " << str3 << std::endl;
  // move semantic
  str3= std::move(str1);
  std::cout << "str3= std::move(str1);\n";
  std::cout << "str1= " << str1 << std::endl;
  std::cout << "str3= " << str3 << std::endl;
  std::cout << "\n";
}

Explanation

In the above example, we demonstrated how the value of str1 can be transferred to strings using two different methods: copy semantic and move semantic.

  • In line 18, we used the copy semantic, and the string "ABCDEF" is present in both str1 and str2. We can, therefore, say that the value has ...