Reference

function template
<memory>

std::make_shared

template <class T, class... Args> shared_ptr<T> make_shared (Args&&... args);
Make shared_ptr
Allocates and constructs an object of type T passing args to its constructor, and returns an object of type shared_ptr<T> that owns and stores a pointer to it (with a use count of 1).

This function uses ::new to allocate storage for the object. A similar function, allocate_shared, accepts an allocator as argument and uses it to allocate the storage.

Parameters

args
List of elements passed to T's constructor.
Args is a list of zero or more types.

Return Value

A shared_ptr object that owns and stores a pointer to a newly allocated object of type T.

Example

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// make_shared example
#include <iostream>
#include <memory>
int main () {
 std::shared_ptr<int> foo = std::make_shared<int> (10);
 // same as:
 std::shared_ptr<int> foo2 (new int(10));
 auto bar = std::make_shared<int> (20);
 auto baz = std::make_shared<std::pair<int,int>> (30,40);
 std::cout << "*foo: " << *foo << '\n';
 std::cout << "*bar: " << *bar << '\n';
 std::cout << "*baz: " << baz->first << ' ' << baz->second << '\n';
 return 0;
}

Output:
*foo: 10
*bar: 20
*baz: 30 40


See also

allocate_shared
Allocate shared_ptr (function template)
shared_ptr::shared_ptr
Construct shared_ptr (public member function)
shared_ptr::operator=
shared_ptr assignment (public member function)

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