.TH "std::shared_ptr< _Tp >" 3cxx "Fri May 28 2021" "libstdc++" \" -*- nroff -*-
.ad l
.nh
.SH NAME
std::shared_ptr< _Tp > \- A smart pointer with reference-counted copy semantics\&.  

.SH SYNOPSIS
.br
.PP
.PP
Inherits std::__shared_ptr< _Tp, _Lp >\&.
.SS "Public Types"

.in +1c
.ti -1c
.RI "using \fBelement_type\fP = typename __shared_ptr< _Tp >::element_type"
.br
.in -1c
.SS "Public Member Functions"

.in +1c
.ti -1c
.RI "constexpr \fBshared_ptr\fP () noexcept"
.br
.RI "Construct an empty shared_ptr\&. "
.ti -1c
.RI "template<typename _Yp , typename  = _Constructible<_Yp*>> \fBshared_ptr\fP (_Yp *__p)"
.br
.RI "Construct a shared_ptr that owns the pointer \fI__p\fP\&. "
.ti -1c
.RI "template<typename _Yp , typename _Deleter , typename  = _Constructible<_Yp*, _Deleter>> \fBshared_ptr\fP (_Yp *__p, _Deleter __d)"
.br
.RI "Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. "
.ti -1c
.RI "template<typename _Yp , typename _Deleter , typename _Alloc , typename  = _Constructible<_Yp*, _Deleter, _Alloc>> \fBshared_ptr\fP (_Yp *__p, _Deleter __d, _Alloc __a)"
.br
.RI "Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. "
.ti -1c
.RI "\fBshared_ptr\fP (const \fBshared_ptr\fP &) noexcept=default"
.br
.ti -1c
.RI "template<typename _Yp , typename  = _Constructible<const shared_ptr<_Yp>&>> \fBshared_ptr\fP (const \fBshared_ptr\fP< _Yp > &__r) noexcept"
.br
.RI "If \fI__r\fP is empty, constructs an empty shared_ptr; otherwise construct a shared_ptr that shares ownership with \fI__r\fP\&. "
.ti -1c
.RI "template<typename _Yp > \fBshared_ptr\fP (const \fBshared_ptr\fP< _Yp > &__r, element_type *__p) noexcept"
.br
.RI "Constructs a shared_ptr instance that stores \fI__p\fP and shares ownership with \fI__r\fP\&. "
.ti -1c
.RI "template<typename _Yp , typename  = _Constructible<const weak_ptr<_Yp>&>> \fBshared_ptr\fP (const \fBweak_ptr\fP< _Yp > &__r)"
.br
.RI "Constructs a shared_ptr that shares ownership with \fI__r\fP and stores a copy of the pointer stored in \fI__r\fP\&. "
.ti -1c
.RI "template<typename _Deleter > \fBshared_ptr\fP (nullptr_t __p, _Deleter __d)"
.br
.RI "Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. "
.ti -1c
.RI "template<typename _Deleter , typename _Alloc > \fBshared_ptr\fP (nullptr_t __p, _Deleter __d, _Alloc __a)"
.br
.RI "Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. "
.ti -1c
.RI "constexpr \fBshared_ptr\fP (nullptr_t) noexcept"
.br
.RI "Construct an empty shared_ptr\&. "
.ti -1c
.RI "\fBshared_ptr\fP (\fBshared_ptr\fP &&__r) noexcept"
.br
.RI "Move-constructs a shared_ptr instance from \fI__r\fP\&. "
.ti -1c
.RI "template<typename _Yp , typename  = _Constructible<shared_ptr<_Yp>>> \fBshared_ptr\fP (\fBshared_ptr\fP< _Yp > &&__r) noexcept"
.br
.RI "Move-constructs a shared_ptr instance from \fI__r\fP\&. "
.ti -1c
.RI "template<typename _Tp1 , typename > \fBshared_ptr\fP (\fBstd::auto_ptr\fP< _Tp1 > &&__r)"
.br
.ti -1c
.RI "template<typename _Yp , typename _Del , typename  = _Constructible<unique_ptr<_Yp, _Del>>> \fBshared_ptr\fP (\fBunique_ptr\fP< _Yp, _Del > &&__r)"
.br
.ti -1c
.RI "element_type * \fBget\fP () const noexcept"
.br
.ti -1c
.RI "\fBoperator bool\fP () const"
.br
.ti -1c
.RI "element_type & \fBoperator*\fP () const noexcept"
.br
.ti -1c
.RI "element_type * \fBoperator\->\fP () const noexcept"
.br
.ti -1c
.RI "\fBshared_ptr\fP & \fBoperator=\fP (const \fBshared_ptr\fP &) noexcept=default"
.br
.ti -1c
.RI "template<typename _Yp > _Assignable< const \fBshared_ptr\fP< _Yp > & > \fBoperator=\fP (const \fBshared_ptr\fP< _Yp > &__r) noexcept"
.br
.ti -1c
.RI "\fBshared_ptr\fP & \fBoperator=\fP (\fBshared_ptr\fP &&__r) noexcept"
.br
.ti -1c
.RI "template<class _Yp > _Assignable< \fBshared_ptr\fP< _Yp > > \fBoperator=\fP (\fBshared_ptr\fP< _Yp > &&__r) noexcept"
.br
.ti -1c
.RI "template<typename _Yp , typename _Del > _Assignable< \fBunique_ptr\fP< _Yp, _Del > > \fBoperator=\fP (\fBunique_ptr\fP< _Yp, _Del > &&__r)"
.br
.ti -1c
.RI "template<typename _Tp1 > bool \fBowner_before\fP (__shared_ptr< _Tp1, _Lp > const &__rhs) const noexcept"
.br
.ti -1c
.RI "template<typename _Tp1 > bool \fBowner_before\fP (__weak_ptr< _Tp1, _Lp > const &__rhs) const noexcept"
.br
.ti -1c
.RI "void \fBreset\fP () noexcept"
.br
.ti -1c
.RI "template<typename _Yp > _SafeConv< _Yp > \fBreset\fP (_Yp *__p)"
.br
.ti -1c
.RI "template<typename _Yp , typename _Deleter > _SafeConv< _Yp > \fBreset\fP (_Yp *__p, _Deleter __d)"
.br
.ti -1c
.RI "template<typename _Yp , typename _Deleter , typename _Alloc > _SafeConv< _Yp > \fBreset\fP (_Yp *__p, _Deleter __d, _Alloc __a)"
.br
.ti -1c
.RI "void \fBswap\fP (__shared_ptr< _Tp, _Lp > &__other) noexcept"
.br
.ti -1c
.RI "bool \fBunique\fP () const noexcept"
.br
.ti -1c
.RI "long \fBuse_count\fP () const noexcept"
.br
.in -1c
.SS "Friends"

.in +1c
.ti -1c
.RI "template<typename _Yp , typename _Alloc , typename\&.\&.\&. _Args> \fBshared_ptr\fP< _Yp > \fBallocate_shared\fP (const _Alloc &__a, _Args &&\&.\&.\&. __args)"
.br
.RI "Create an object that is owned by a shared_ptr\&. "
.ti -1c
.RI "class \fBweak_ptr< _Tp >\fP"
.br
.in -1c
.SH "Detailed Description"
.PP 

.SS "template<typename _Tp>
.br
class std::shared_ptr< _Tp >"
A smart pointer with reference-counted copy semantics\&. 

The object pointed to is deleted when the last shared_ptr pointing to it is destroyed or reset\&. 
.PP
Definition at line 103 of file bits/shared_ptr\&.h\&.
.SH "Constructor & Destructor Documentation"
.PP 
.SS "template<typename _Tp > constexpr \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP ()\fC [inline]\fP, \fC [constexpr]\fP, \fC [noexcept]\fP"

.PP
Construct an empty shared_ptr\&. 
.PP
\fBPostcondition\fP
.RS 4
use_count()==0 && get()==0 
.RE
.PP

.PP
Definition at line 127 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp , typename  = _Constructible<_Yp*>> \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (_Yp * __p)\fC [inline]\fP, \fC [explicit]\fP"

.PP
Construct a shared_ptr that owns the pointer \fI__p\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A pointer that is convertible to element_type*\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fCdelete\fP \fI__p\fP is called\&. 
.RE
.PP

.PP
Definition at line 139 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp , typename _Deleter , typename  = _Constructible<_Yp*, _Deleter>> \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (_Yp * __p, _Deleter __d)\fC [inline]\fP"

.PP
Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A pointer\&. 
.br
\fI__d\fP A deleter\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw
.PP
__shared_ptr will release __p by calling __d(__p) 
.PP
Definition at line 156 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Deleter > \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (nullptr_t __p, _Deleter __d)\fC [inline]\fP"

.PP
Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A null pointer constant\&. 
.br
\fI__d\fP A deleter\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw
.PP
The last owner will call __d(__p) 
.PP
Definition at line 173 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp , typename _Deleter , typename _Alloc , typename  = _Constructible<_Yp*, _Deleter, _Alloc>> \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (_Yp * __p, _Deleter __d, _Alloc __a)\fC [inline]\fP"

.PP
Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A pointer\&. 
.br
\fI__d\fP A deleter\&. 
.br
\fI__a\fP An allocator\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw _Alloc's copy constructor and destructor must not throw\&.
.PP
__shared_ptr will release __p by calling __d(__p) 
.PP
Definition at line 193 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Deleter , typename _Alloc > \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (nullptr_t __p, _Deleter __d, _Alloc __a)\fC [inline]\fP"

.PP
Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A null pointer constant\&. 
.br
\fI__d\fP A deleter\&. 
.br
\fI__a\fP An allocator\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw _Alloc's copy constructor and destructor must not throw\&.
.PP
The last owner will call __d(__p) 
.PP
Definition at line 212 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp > \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (const \fBshared_ptr\fP< _Yp > & __r, element_type * __p)\fC [inline]\fP, \fC [noexcept]\fP"

.PP
Constructs a shared_ptr instance that stores \fI__p\fP and shares ownership with \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr\&. 
.br
\fI__p\fP A pointer that will remain valid while \fI*__r\fP is valid\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
get() == __p && use_count() == __r\&.use_count()
.RE
.PP
This can be used to construct a \fCshared_ptr\fP to a sub-object of an object managed by an existing \fCshared_ptr\fP\&.
.PP
.PP
.nf
shared_ptr< pair<int,int> > pii(new pair<int,int>());
shared_ptr<int> pi(pii, &pii->first);
assert(pii\&.use_count() == 2);
.fi
.PP
 
.PP
Definition at line 234 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp , typename  = _Constructible<const shared_ptr<_Yp>&>> \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (const \fBshared_ptr\fP< _Yp > & __r)\fC [inline]\fP, \fC [noexcept]\fP"

.PP
If \fI__r\fP is empty, constructs an empty shared_ptr; otherwise construct a shared_ptr that shares ownership with \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
get() == __r\&.get() && use_count() == __r\&.use_count() 
.RE
.PP

.PP
Definition at line 246 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (\fBshared_ptr\fP< _Tp > && __r)\fC [inline]\fP, \fC [noexcept]\fP"

.PP
Move-constructs a shared_ptr instance from \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr rvalue\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
*this contains the old value of \fI__r\fP, \fI__r\fP is empty\&. 
.RE
.PP

.PP
Definition at line 254 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp , typename  = _Constructible<shared_ptr<_Yp>>> \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (\fBshared_ptr\fP< _Yp > && __r)\fC [inline]\fP, \fC [noexcept]\fP"

.PP
Move-constructs a shared_ptr instance from \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr rvalue\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
*this contains the old value of \fI__r\fP, \fI__r\fP is empty\&. 
.RE
.PP

.PP
Definition at line 263 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > template<typename _Yp , typename  = _Constructible<const weak_ptr<_Yp>&>> \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (const \fBweak_ptr\fP< _Yp > & __r)\fC [inline]\fP, \fC [explicit]\fP"

.PP
Constructs a shared_ptr that shares ownership with \fI__r\fP and stores a copy of the pointer stored in \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A weak_ptr\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == __r\&.use_count() 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIbad_weak_ptr\fP when __r\&.expired(), in which case the constructor has no effect\&. 
.RE
.PP

.PP
Definition at line 275 of file bits/shared_ptr\&.h\&.
.SS "template<typename _Tp > constexpr \fBstd::shared_ptr\fP< _Tp >::\fBshared_ptr\fP (nullptr_t)\fC [inline]\fP, \fC [constexpr]\fP, \fC [noexcept]\fP"

.PP
Construct an empty shared_ptr\&. 
.PP
\fBPostcondition\fP
.RS 4
use_count() == 0 && get() == nullptr 
.RE
.PP

.PP
Definition at line 307 of file bits/shared_ptr\&.h\&.
.SH "Friends And Related Function Documentation"
.PP 
.SS "template<typename _Tp > template<typename _Yp , typename _Alloc , typename\&.\&.\&. _Args> \fBshared_ptr\fP<_Yp> allocate_shared (const _Alloc & __a, _Args &&\&.\&.\&. __args)\fC [friend]\fP"

.PP
Create an object that is owned by a shared_ptr\&. 
.PP
\fBParameters\fP
.RS 4
\fI__a\fP An allocator\&. 
.br
\fI__args\fP Arguments for the \fI_Tp\fP object's constructor\&. 
.RE
.PP
\fBReturns\fP
.RS 4
A shared_ptr that owns the newly created object\&. 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIAn\fP exception thrown from \fI_Alloc::allocate\fP or from the constructor of \fI_Tp\fP\&.
.RE
.PP
A copy of \fI__a\fP will be used to allocate memory for the shared_ptr and the new object\&. 
.PP
Definition at line 699 of file bits/shared_ptr\&.h\&.

.SH "Author"
.PP 
Generated automatically by Doxygen for libstdc++ from the source code\&.