std::experimental::ranges:: tagged

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C++
Experimental
Ranges
General utilities library
std::experimental::ranges::tagged
template < class Base, TagSpecifier ... Tags >

requires sizeof... ( Tags ) <= std:: tuple_size < Base > :: value

struct tagged ;
(ranges TS)

The class template tagged augments a tuple-like class type Base , which it publicly derives from, with a set of named accessors specified by the tag specifiers Tags... . The tags are applied in order: the i-th tag specifier in Tags... correspond to the i-th element of the tuple.

The tag specifiers in Tags... shall be unique. Otherwise, the behavior is undefined.

It is not possible to delete an instance of tagged through a pointer to any base other than Base .

Member functions

construct a tagged object
(public member function)
assigns a tagged object
(public member function)
swaps the contents of two tagged objects
(public member function)

Named element accessors

For the N -th tag specifier in Tags... whose corresponding element name is name , tagged provides accessors named name as follows: 

constexpr decltype(auto) name() &       { return std::get<N>(*this); }
constexpr decltype(auto) name() const & { return std::get<N>(*this); }
constexpr decltype(auto) name() &&      { return std::get<N>(std::move(*this)); }

Non-member functions

specializes swap for tagged objects
(function)

Tuple-like access

obtains the size of a tagged
(class template specialization)
obtains the types of the elements of a tagged
(class template specialization)

See also

specifies that a type is a tag specifier
(concept)
alias template for a tagged std::pair
(alias template)
convenience function for creating a tagged_pair
(function template)
alias template for a tagged std::tuple
(alias template)
convenience function for creating a tagged_tuple
(function template)
tag specifiers for use with ranges::tagged
(class)
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