cppdraft_translate/cppdraft/tuple/common/ref.md

[tuple.common.ref]

22 General utilities library [utilities]

22.4 Tuples [tuple]

22.4.10 common_reference related specializations [tuple.common.ref]

1

#

In the descriptions that follow:

• (1.1)

  Let TTypes be a pack formed by the sequence of tuple_element_t<i, TTuple> for every integer 0≤i<tuple_size_v.

• (1.2)

  Let UTypes be a pack formed by the sequence of tuple_element_t<i, UTuple> for every integer 0≤i<tuple_size_v.

🔗

template<[tuple-like](tuple.like#concept:tuple-like "22.4.3 Concept tuple-like [tuple.like]") TTuple, [tuple-like](tuple.like#concept:tuple-like "22.4.3 Concept tuple-like [tuple.like]") UTuple, template<class> class TQual, template<class> class UQual> struct basic_common_reference<TTuple, UTuple, TQual, UQual> { using type = see below; };

2

#

Constraints:

• (2.1)

  TTuple is a specialization of tuple orUTuple is a specialization of tuple.

• (2.2)

  is_same_v<TTuple, decay_t> is true.

• (2.3)

  is_same_v<UTuple, decay_t> is true.

• (2.4)

  tuple_size_v equals tuple_size_v.

• (2.5)

  tuple<common_reference_t<TQual, UQual>...> denotes a type.

The member typedef-name type denotes the typetuple<common_reference_t<TQual, UQual>...>.

🔗

template<[tuple-like](tuple.like#concept:tuple-like "22.4.3 Concept tuple-like [tuple.like]") TTuple, [tuple-like](tuple.like#concept:tuple-like "22.4.3 Concept tuple-like [tuple.like]") UTuple> struct common_type<TTuple, UTuple> { using type = see below; };

3

#

Constraints:

• (3.1)

  TTuple is a specialization of tuple orUTuple is a specialization of tuple.

• (3.2)

  is_same_v<TTuple, decay_t> is true.

• (3.3)

  is_same_v<UTuple, decay_t> is true.

• (3.4)

  tuple_size_v equals tuple_size_v.

• (3.5)

  tuple<common_type_t<TTypes, UTypes>...> denotes a type.

The member typedef-name type denotes the typetuple<common_type_t<TTypes, UTypes>...>.