Variable iox::cxx::INVALID_VARIANT_INDEX

Defined in File variant.hpp

Variable Documentation

static constexpr uint64_t iox::cxx::INVALID_VARIANT_INDEX = std::numeric_limits<uint64_t>::max()

value which an invalid variant index occupies

cxx::variant<int, float> someVariant;

// every unset variant has an invalid variant in the beginning
if ( someVariant.index() == INVALID_VARIANT_INDEX ) ...

cxx::variant<int, float> someVariant2(cxx::in_place_type<int>, 12);

// variant with setted value therefore the index is not invalid
if ( someVariant.index() != INVALID_VARIANT_INDEX ) ...