deduction guides for std::function_ref

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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
  • 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
  • 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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