bsl::variant_alternative

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

NameDescription
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.