std::owner_less

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(until C++17*)

(C++11)

owner_less<void>

(C++17)

owner_hash

(C++26)

owner_equal

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enable_shared_from_this

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Defined in header`<memory>`
template<> struct owner_less<void>;		(since C++17)

std::owner_less<void> is a specialization ofstd::owner_less with parameter types deduced.

[edit]Nested types

Nested type	Definition
`is_transparent`	unspecified

[edit]Member functions

operator()

compares its arguments using owner-based semantics
(function)

std::owner_less<void>::operator()

template<class T,class U> bool operator()(conststd::shared_ptr<T>& lhs, conststd::shared_ptr<U>& rhs)constnoexcept;		(since C++17)
template<class T,class U> bool operator()(conststd::shared_ptr<T>& lhs, conststd::weak_ptr<U>& rhs)constnoexcept;		(since C++17)
template<class T,class U> bool operator()(conststd::weak_ptr<T>& lhs, conststd::shared_ptr<U>& rhs)constnoexcept;		(since C++17)
template<class T,class U> bool operator()(conststd::weak_ptr<T>& lhs, conststd::weak_ptr<U>& rhs)constnoexcept;		(since C++17)

Compareslhs andrhs using owner-based semantics. Effectively callslhs.owner_before(rhs).

The ordering is strict weak ordering relation.

lhs andrhs are equivalent only if they are both empty or share ownership.

Parameters

lhs, rhs

shared-ownership pointers to compare

Return value

true iflhs isless thanrhs as determined by the owner-based ordering.

[edit]Notes

Feature-test macro	Value	Std	Feature
`__cpp_lib_transparent_operators`	`201510L`	(C++17)	Transparentstd::owner_less (std::owner_less<void>)

[edit]See also

owner_before	provides owner-based ordering of shared pointers (public member function of`std::shared_ptr<T>`)[edit]
owner_before	provides owner-based ordering of weak pointers (public member function of`std::weak_ptr<T>`)[edit]