$$ [C++11] $$ In $$ C++11 $$, you can tell the compiler to explicitly generate the default version of a default constructor, copy constructor, move constructor, copy assignment operator, move assignment operator or destructor by following the special member function's prototype with explicit (default) $$ = $$ default default

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In C++11, you can explicitly instruct the compiler to generate the default version of special member functions (like constructors, assignment operators, and destructors) by using the `= default` syntax. This is particularly useful when you want to ensure that a class has a default constructor, copy constructor, move constructor, copy assignment operator, move assignment operator, or destructor, but you don't want to provide a custom implementation.

Here's a breakdown of how to use `= default` for each of these special member functions:

1. **Default Constructor**:
   ```cpp
   class MyClass {
   public:
       MyClass() = default; // Default constructor
   };
   ```

2. **Copy Constructor**:
   ```cpp
   class MyClass {
   public:
       MyClass(const MyClass&) = default; // Copy constructor
   };
   ```

3. **Move Constructor**:
   ```cpp
   class MyClass {
   public:
       MyClass(MyClass&&) = default; // Move constructor
   };
   ```

4. **Copy Assignment Operator**:
   ```cpp
   class MyClass {
   public:
       MyClass& operator=(const MyClass&) = default; // Copy assignment operator
   };
   ```

5. **Move Assignment Operator**:
   ```cpp
   class MyClass {
   public:
       MyClass& operator=(MyClass&&) = default; // Move assignment operator
   };
   ```

6. **Destructor**:
   ```cpp
   class MyClass {
   public:
       ~MyClass() = default; // Destructor
   };
   ```

### Explanation:
- **`= default`**: This tells the compiler to generate the default implementation of the special member function. It is a way to explicitly state that you want the compiler's default behavior rather than providing your own implementation.
- **Use Cases**: This is particularly useful in classes that manage resources (like dynamic memory) where you want to ensure that the default behavior is used, which can help avoid issues like double deletion or resource leaks.

### Example:
Here’s a complete example of a class using all of these special member functions:

```cpp
class MyClass {
public:
    MyClass() = default;                       // Default constructor
    MyClass(const MyClass&) = default;        // Copy constructor
    MyClass(MyClass&&) = default;             // Move constructor
    MyClass& operator=(const MyClass&) = default; // Copy assignment operator
    MyClass& operator=(MyClass&&) = default; // Move assignment operator
    ~MyClass() = default;                      // Destructor
};
```

In this example, `MyClass` will have all the special member functions generated by the compiler, ensuring that it behaves correctly with respect to copying and moving.
In C++11, you can use `= default` to let the compiler generate default versions of special member functions like constructors and assignment operators. This ensures that the compiler handles these functions without you providing custom implementations.

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