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

 

C++

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pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
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Dynamic memory management

Smart pointers unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (until C++17) owner_less (C++11) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) Allocators allocator allocator_traits (C++11) allocator_arg_t (C++11) allocator_arg (C++11) uses_allocator (C++11) uses_allocator_construction_args (C++20) make_obj_using_allocator (C++20) uninitialized_construct_using_allocator (C++20) scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) Memory resources pmr::memory_resource (C++17) pmr::get_default_resource (C++17) pmr::set_default_resource (C++17) pmr::new_delete_resource (C++17) pmr::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17) pmr::monotonic_buffer_resource (C++17) pmr::pool_options (C++17)

Uninitialized storage uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) destroy_at (C++17) raw_storage_iterator (until C++20) get_temporary_buffer (until C++20) return_temporary_buffer (until C++20) Garbage collection support declare_reachable (C++11) undeclare_reachable (C++11) declare_no_pointers (C++11) undeclare_no_pointers (C++11) pointer_safety (C++11) get_pointer_safety (C++11) Miscellaneous pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C Library malloc aligned_alloc (C++17) calloc realloc free Low level memory management

 

std::unique_ptr

Member functions

unique_ptr::unique_ptr

unique_ptr::~unique_ptr

unique_ptr::operator=

Modifiers

unique_ptr::release

unique_ptr::reset

unique_ptr::swap

Observers

unique_ptr::get

unique_ptr::get_deleter

unique_ptr::operator bool

unique_ptr::operator*unique_ptr::operator->

unique_ptr::operator[]

Non-member functions

make_uniquemake_unique_default_init (C++14)(C++20)

operator==operator!=operator<operator>operator<=operator>operator>=

operator<< (C++20)

std::swap

std::hash

 

template <class CharT, class Traits, class Y, class D> std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os,                                               const std::unique_ptr<Y, D>& p);		(since C++20)

Inserts the value of the pointer managed by p into the output stream os.

Equivalent to os << p.get().

This overload only participates in overload resolution if os << p.get() is a valid expression.

Parameters

os	-	a std::basic_ostream to insert p into
p	-	the pointer to be inserted into os

Return value

os

Notes

If std::unique_ptr<Y, D>::pointer is a pointer to a character type (e.g., when Y is char or char[] or CharT), this may end up calling the overloads of operator<< for null-terminated character strings (causing undefined behavior if the pointer does not in fact point to such a string), rather than the overload for printing the value of the pointer itself.

Example

Run this code

#include <iostream>
#include <memory>
 
class Foo {};
 
int main()
{
    auto p = std::make_unique<Foo>();
    std::cout << p << '\n';
    std::cout << p.get() << '\n';
}

Possible output:

0x6d9028
0x6d9028

See also

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