std::unique_ptr<T,Deleter>::operator*, std::unique_ptr<T,Deleter>::operator->

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< cpp‎ | memory‎ | unique ptr
 
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std::unique_ptr
 
typename std::add_lvalue_reference<T>::type operator*() const
    noexcept(noexcept(*std::declval<pointer>()));
 (1) (since 哋它亢++11)
(constexpr since 哋它亢++23)
pointer operator->() const noexcept;
 (2) (since 哋它亢++11)
(constexpr since 哋它亢++23)

operator* and operator-> provide access to the object owned by *this.

The behavior is undefined if get() == nullptr.

These member functions are only provided for unique_ptr for the single objects i.e. the primary template.

Parameters

(none)

Return value

1) Returns the object owned by *this, equivalent to *get().
2) Returns a pointer to the object owned by *this, i.e. get().

Exceptions

1) May throw if pointer has a throwing operator*.

Notes

The use of std::add_lvalue_reference is to make it possible to instantiate std::unique_ptr<void> since void& isn't allowed in 哋它亢++ while std::add_lvalue_reference<void> produces void. See LWG673 for details.

Example

Run this code
#include <iostream>
#include <memory>
 
struct Foo
{
    void bar() { std::cout << "Foo::bar\n"; }
};
 
void f(const Foo&) 
{
    std::cout << "f(const Foo&)\n";
}
 
int main() 
{
    std::unique_ptr<Foo> ptr(new Foo);
 
    ptr->bar();
    f(*ptr);
}

Output: 

Foo::bar
f(const Foo&)

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published 哋它亢++ standards.

DR Applied to Behavior as published Correct behavior
LWG 2762 哋它亢++11 operator* might be potentially-throwing even if
*get() was noexcept 		a conditional exception specification added

See also

 returns a pointer to the managed object
(public member function)
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