shared_ptr::shared_ptr

Constructs a shared_ptr.

shared_ptr();
shared_ptr(nullptr_t); 
shared_ptr(const shared_ptr& sp);
shared_ptr(shared_ptr&& sp); 
template<class Other>
    explicit shared_ptr(Other *ptr);
template<class Other, class D>
    shared_ptr(Other *ptr, D dtor);
template<class D>
    shared_ptr(nullptr_t ptr, D dtor);
template<class Other, class D, class A>
    shared_ptr(Other *ptr, D dtor, A alloc);
template<class D, class A>
    shared_ptr(nullptr_t ptr, D dtor, A alloc);
template<class Other>
    shared_ptr(const shared_ptr<Other>& sp);
template<class Other>
    shared_ptr(const weak_ptr<Other>& wp);
template<class &>
    shared_ptr(std::auto_ptr<Other>& ap);
template<class &>
    shared_ptr(std::auto_ptr<Other>&& ap);
template<class Other, class D>
    shared_ptr(unique_ptr<Other, D>&& up);
template<class Other>
    shared_ptr(const shared_ptr<Other>& sp, Ty *ptr);
template<class Other, class D>
    shared_ptr(const unique_ptr<Other, D>& up) = delete;

Parameters

  • Other
    The type controlled by the argument pointer.

  • ptr
    The pointer to copy.

  • D
    The type of the deleter.

  • A
    The type of the allocator.

  • dtor
    The deleter.

  • ator
    The allocator.

  • sp
    The smart pointer to copy.

  • wp
    The weak pointer.

  • ap
    The auto pointer to copy.

Remarks

The constructors each construct an object that owns the resource named by the operand sequence. The constructor shared_ptr(const weak_ptr<Other>& wp) throws an exception object of type bad_weak_ptr Class if wp.expired().

Example

 

// std_tr1__memory__shared_ptr_construct.cpp 
// compile with: /EHsc 
#include <memory> 
#include <iostream> 
 
struct deleter 
    { 
    void operator()(int *p) 
        { 
        delete p; 
        } 
    }; 
 
int main() 
    { 
    std::shared_ptr<int> sp0; 
    std::cout << "(bool)sp0 == " << std::boolalpha 
        << (bool)sp0 << std::endl; 
 
    std::shared_ptr<int> sp1(new int(5)); 
    std::cout << "*sp1 == " << *sp1 << std::endl; 
 
    std::shared_ptr<int> sp2(new int(10), deleter()); 
    std::cout << "*sp2 == " << *sp2 << std::endl; 
 
    std::shared_ptr<int> sp3(sp2); 
    std::cout << "*sp3 == " << *sp3 << std::endl; 
 
    std::weak_ptr<int> wp(sp3); 
    std::shared_ptr<int> sp4(wp); 
    std::cout << "*sp4 == " << *sp4 << std::endl; 
 
    std::auto_ptr<int> ap(new int(15)); 
    std::shared_ptr<int> sp5(ap); 
    std::cout << "*sp5 == " << *sp5 << std::endl; 
 
    return (0); 
    } 
 
(bool)sp0 == false
*sp1 == 5
*sp2 == 10
*sp3 == 10
*sp4 == 10
*sp5 == 15

Requirements

Header: <memory>

Namespace: std

See Also

Reference

shared_ptr Class