std::experimental::invocation_type,std::experimental::raw_invocation_type

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Experimental

Technical Specification
Filesystem library(filesystem TS)
Library fundamentals(library fundamentals TS)
Library fundamentals 2(library fundamentals TS v2)
Library fundamentals 3(library fundamentals TS v3)
Extensions for parallelism(parallelism TS)
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Library fundamentals

experimental::optional
experimental::any
experimental::basic_string_view
experimental::sample
experimental::shared_ptr
experimental::weak_ptr
experimental::apply
experimental::invocation_typeexperimental::raw_invocation_type
experimental::search
experimental::default_searcherexperimental::make_default_searcher
experimental::boyer_moore_searcherexperimental::make_boyer_moore_searcher
experimental::boyer_moore_horspool_searcherexperimental::make_boyer_moore_horspool_searcher
Type-erased and polymorphic allocators
Variable templates for type traits

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Defined in header`<experimental/type_traits>`
template<class> struct raw_invocation_type;//undefined template<class Fn,class...ArgTypes> struct raw_invocation_type<Fn(ArgTypes...)>;	(1)	(library fundamentals TS)
template<class> struct invocation_type;//undefined template<class Fn,class...ArgTypes> struct invocation_type<Fn(ArgTypes...)>;	(2)	(library fundamentals TS)

Computes theinvocation parameters whenFn is called with the argumentsArgTypes..., as inINVOKE(std::declval<Fn>(),std::declval<ArgTypes>()...), whereINVOKE is the operation defined inCallable.

Theinvocation parameters of the expressionINVOKE(f, t1, t2, ..., tN) is defined as follows, whereT1 is the (possibly cv-qualified) type oft1 andU1 isT1& ift1 is an lvalue andT1&& otherwise:

Iff is a pointer to a member function of a classT, then the invocation parameters areU1 followed by the parameters off matched byt2, ..., tN.
IfN == 1 andf is a pointer to member data of a classT, then the invocation parameter isU1.
Iff is an object of class type, the invocation parameters are the parameters matchingt1, ..., tN of the best viable function for the argumentst1, ..., tN among the function call operators and surrogate call functions off.
In all other cases, the invocations parameters are the parameters off matchingt1, ..., tN.

If an argumenttI matches an ellipsis in the function's parameter list, the corresponding invocation parameter is the result of applying the default argument promotions totI.

Fn and all types inArgTypes can be any complete type, array of unknown bound, or (possibly cv-qualified)void.

[edit]Member types

Member type Definition

raw_invocation_type<Fn(ArgTypes...)>::type

R(T1, T2, ...), where:

R isstd::result_of_t<Fn(ArgTypes...)>.
T1, T2, ... are theinvocation parameters ofINVOKE(std::declval<Fn>(),std::declval<ArgTypes>()...) as defined above.

Only defined ifFn can be called with the argumentsArgTypes... in unevaluated context.

invocation_type<Fn(ArgTypes...)>::type

R(U1, U2, ...), where

R isstd::result_of_t<Fn(ArgTypes...)>.
T1, T2, ... are theinvocation parameters ofINVOKE(std::declval<Fn>(),std::declval<ArgTypes>()...) as defined above.
A1, A2, ... denotesArgTypes...
Ui isstd::decay_t<Ai> ifstd::declval<Ai>() is an rvalue andTi otherwise.

Only defined ifFn can be called with the argumentsArgTypes... in unevaluated context.

[edit]Helper types

template<class T> using raw_invocation_type_t=typename raw_invocation_type<T>::type;		(library fundamentals TS)
template<class T> using invocation_type_t=typename invocation_type<T>::type;		(library fundamentals TS)