std::make_unique in C++ 14

std::make_unique is a utility function in C++ that was introduced in C++14. It is used to create a unique_ptr object, which is a smart pointer that manages the lifetime of dynamically allocated objects. It is defined inside <memory> header file.

Syntax

std::make_unique <object_type> (arguments);

Parameters

object_type: It is the type of object you want to create.
arguments: It is the argument list for the constructor of object_type.

Return Type

This function returns a unique_ptr of type object_type.

It is the preferred way to create a std::unique_ptr, as it is safer than using the new operator directly because the object is automatically destroyed when it goes out of scope.

Examples of std::make_unique

The following programs demonstrate how to implement std::make_unique() in our programs.

Example 1

C++

// C++ code to implement std::make_unique() 
#include <iostream> 
#include <memory> 

using namespace std; 

class Geeks { 

public: 

    Geeks() { cout << "Object Created\n"; }  // constructor 

    ~Geeks() { cout << "Object Destroyed"; }  // destructor 
}; 

void f() 
{ 

      // creating unique ptr object 

    unique_ptr<Geeks> o = make_unique<Geeks>(); 
} 

int main() 
{ 

    f(); 

    return 0; 
}

Output

Object Created
Object Destroyed

Example 2

C++14

// C++ code to implement std::make_unique() 
#include <iostream> 
#include <memory> 

using namespace std; 

class Geeks { 

public: 

    int d; 

    // construtor 

    Geeks(int x) 

    { 

        this->d = x; 

        cout << "Object Created\n"; 

    } 

    // destructor 

    ~Geeks() { cout << "Object Destroyed"; } 
}; 

void f() 
{ 

    // creating unique ptr object 

    unique_ptr<Geeks> o = make_unique<Geeks>(10); 

    cout << o->d << endl; 
} 

int main() 
{ 

    f(); 

    return 0; 
}