std::function_ref::operator=

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<cpp‎ |utility‎ |functional‎ |function ref

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rel_ops::operator!=rel_ops::operator>

rel_ops::operator<=rel_ops::operator>=

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cmp_equalcmp_lesscmp_less_than

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Partial function application
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logical_and
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Transparent operator wrappers

plus<> (C++14)
minus<> (C++14)
negate<> (C++14)
multiplies<> (C++14)
divides<> (C++14)
modulus<> (C++14)
bit_and<> (C++14)
bit_or<> (C++14)
bit_not<> (C++14)
bit_xor<> (C++14)

equal_to<> (C++14)
not_equal_to<> (C++14)
greater<> (C++14)
less<> (C++14)
greater_equal<> (C++14)
less_equal<> (C++14)
logical_and<> (C++14)
logical_or<> (C++14)
logical_not<> (C++14)

Negators
not_fn (C++17)
Searchers
default_searcher (C++17)
boyer_moore_searcher (C++17)
boyer_moore_horspool_searcher (C++17)

Constrained comparators
ranges::equal_to (C++20)
ranges::not_equal_to (C++20)
ranges::greater (C++20)
ranges::less (C++20)
ranges::greater_equal (C++20)
ranges::less_equal (C++20)
compare_three_way (C++20)

Old binders and adaptors

unary_function (until C++17*)
binary_function (until C++17*)
ptr_fun (until C++17*)
pointer_to_unary_function (until C++17*)
pointer_to_binary_function (until C++17*)
mem_fun (until C++17*)
mem_fun_tmem_fun1_tconst_mem_fun_tconst_mem_fun1_t (until C++17)(until C++17)(until C++17)(until C++17)
not1 (until C++20*)
not2 (until C++20*)

binder1stbinder2nd (until C++17)(until C++17)
bind1stbind2nd (until C++17)(until C++17)

mem_fun_ref (until C++17*)
mem_fun_ref_tmem_fun1_ref_tconst_mem_fun_ref_tconst_mem_fun1_ref_t (until C++17)(until C++17)(until C++17)(until C++17)
unary_negate (until C++20*)
binary_negate (until C++20*)

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std::function_ref

Member functions
function_ref::function_ref
function_ref::operator=
function_ref::operator()
Deduction guides

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constexpr function_ref& operator=(const function_ref&)noexcept=default;	(1)	(since C++26)
template<class T> constexpr function_ref& operator=( T)= delete;	(2)	(since C++26)

1) Copy assignment operator is explicitly-defaulted.std::function_ref satisfiescopyable andTriviallyCopyable. This defaulted assignment operator performs a shallow copy of the storedthunk-ptr andbound-entity.

2) User-defined assignment operator is explicitly-deleted ifT is not the same type asstd::function_ref,std::is_pointer_v<T> isfalse, andT is not a specialization ofstd::nontype_t. This overload participates in overload resolution only if the constraints are satisfied in the conditions above.

[edit]Return value

*this

[edit]See also

(constructor)	constructs a new`function_ref` object (public member function)[edit]
operator=	replaces or destroys the target (public member function of`std::copyable_function`)[edit]
operator=	assigns a new target (public member function of`std::function<R(Args...)>`)[edit]
operator=	replaces or destroys the target (public member function of`std::move_only_function`)[edit]

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std::function_ref::operator=

[edit]Return value

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