Compute the type of the alternative at index t_INDEX.

Synopsis

Declared in <bslstl_variant.h>

template<
    std::size_t t_INDEX,
    class t_TYPE>
struct variant_alternative;

Description

This metafunction calculates the type of the alternative whose index is (template parameter) t_INDEX in the possibly cv‐qualified bsl::variant type of (template parameter) t_TYPE.

If t_TYPE is cv‐qualified, its cv‐qualifiers are applied to the alternative.

Specializations

Name

Description

variant_alternative<t_INDEX, t_TYPE volatile>

Strip volatile from t_TYPE before computing the alternative type.

variant_alternative<t_INDEX, t_TYPE const>

Strip const from t_TYPE before computing the alternative type.

variant_alternative<t_INDEX, t_TYPE const volatile>

Strip const volatile from t_TYPE before computing the alternative type.

variant_alternative<t_INDEX, variant<t_HEAD, t_TAIL...>>

Compute the alternative type at index t_INDEX of a bsl::variant.

Created with MrDocs