std::experimental::ranges::tagged_pair
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                    < cpp | experimental | ranges
                    
                                                            
                    |   Defined in header  <experimental/ranges/utility>
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|   template< TaggedType T1, TaggedType T2 > using tagged_pair = /* see below */;  | 
(ranges TS) | |
Convenience alias template for naming a ranges::tagged wrapping a std::pair.
A TaggedType is a function type S(T), where S is a TagSpecifier and T is the type of the element.
tagged_pair<S1(T1), S2(T2)> is an alias for ranges::tagged<std::pair<T1, T2>, S1, S2>.
Notes
Because a function type is used to "glue" the tag specifier and the corresponding element type together, the usual parameter type adjustments apply. In particular, top-level cv-qualifiers are removed and array types are adjusted to pointers: tagged_pair<tag::in(const int* const), tag::out(int[])> is ranges::tagged<std::pair<const int*, int*>, tag::in, tag::out>.
See also
|    specifies that a type represents a tag specifier and its element type   (concept)  | |
|    augument a tuple-like type with named accessors   (class 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)  |