std::experimental::ranges::tag::in, in1, in2, out, out1, out2, fun, min, max, begin, end

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struct in { /* implementation-defined */ } ;

struct in1 { /* implementation-defined */ } ;
struct in2 { /* implementation-defined */ } ;
struct out { /* implementation-defined */ } ;
struct out1 { /* implementation-defined */ } ;
struct out2 { /* implementation-defined */ } ;
struct fun { /* implementation-defined */ } ;
struct min { /* implementation-defined */ } ;
struct max { /* implementation-defined */ } ;
struct begin { /* implementation-defined */ } ;

struct end { /* implementation-defined */ } ;
(ranges TS)

These classes are TagSpecifiers for use with ranges::tagged

The name of a specifier is also the element name it corresponds to. For instance, ranges::tagged < std::pair < int, int >, tag:: min, tag:: max > provides a set of named accessors named min and a set of named accessors named max