deduction guides for std::function_ref

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C++
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Relational operators (deprecated in C++20)
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(C++17) (C++23)
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Old binders and adaptors
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std::function_ref
Defined in header <functional>
template < class F >
function_ref ( F * ) - > function_ref < F > ;
(1) (since C++26)
template < auto f >
function_ref ( std:: nontype_t < f > ) - > function_ref < /*see below*/ > ;
(2) (since C++26)
template < auto f, class T >
function_ref ( std:: nontype_t < f > , T && ) - > function_ref < /*see below*/ > ;
(3) (since C++26)
1) This overload participates in overload resolution only if std:: is_function_v < F > is true .
2) Let type F be std:: remove_pointer_t < decltype ( f ) > . This overload participates in overload resolution only if std:: is_function_v < F > is true . The deduced type is std:: function_ref < F > .
3) Let type F be decltype ( f ) . This overload participates in overload resolution only if :
  • F is of the form R ( G :: * ) ( A... ) noexcept ( E ) (optionally cv-qualified, optionally noexcept, optionally lvalue reference qualified) for a type G , or
  • F is of the form M G :: * for a type G and an object type M , in which case let R be std:: invoke_result_t < F, T & > , A... be an empty pack, and E be false, or
  • F is of the form R ( * ) ( G, A... ) noexcept ( E ) for a type G .
The deduced type is std:: function_ref < R ( A... ) noexcept ( E ) > .

Example

This section is incomplete
Reason: no example
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