tuple

20.41.0

A fixed-size collection of heterogeneous values.

STL equivalent: std::tuple

Adds additional functionality to std::tuple.

etl::tuple<typename... Types>

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Template deduction guides

C++17 and above

Template deduction guide from variadic arguments.

template <typename... TArgs>

tuple(TArgs... args) -> tuple<TArgs...>;

Template deduction guide from pair.

template <typename T1, typename T2>

tuple(ETL_OR_STD::pair<T1, T2>) -> tuple<T1, T2>;

Example

etl::tuple tp(1, 2.2, 3, std::string("4"));

Equivalent to:

etl::tuple<int, double, int, std::string> t(1, 2.2, 3, std::string("4"));

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Make tuple

template <typename... Types>

ETL_NODISCARD

ETL_CONSTEXPR14

etl::tuple<etl::unwrap_ref_decay_t<Types>...> make_tuple(Types&&... args)

Example

auto t = etl::make_tuple(1, 2.2, 3, std::string("4"));

Equivalent to:

etl::tuple<int, double, int, std::string> t(1, 2.2, 3, std::string("4"));

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Member types

value_type The first type contained by this tuple.

this_type The type of this tuple.

base_type The type of the base tuple to this tuple. This is a tuple of all types except for the first.

index_sequence_type The index_sequence type for this tuple.

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Constructor

Default or copy constructs each element.

Can be initialised like a C array.

etl::array<int, 10> data = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 };

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Access

template <size_t Index, typename Tuple>

etl::tuple_element;

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Capacity

template <typename Tuple>

struct tuple_size;

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ETL Extensions

template <typename T>

struct is_tuple

If T is a tuple etl::is_tuple is defined as etl::true_type, otherwise etl::false_type.

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Specialisations of STL to allow the use of C++ structured bindings.

template <typename... Types>

struct tuple_size<etl::tuple<Types...>>

Specialisation of tuple_size to allow the use of C++ structured bindings.

Declared in namespace std.

template <size_t Index, typename... Types>

struct tuple_element<Index, etl::tuple<Types...>>

Specialisation of tuple_element to allow the use of C++ structured bindings.

Declared in namespace std.

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Convert an etl::tuple to a std::tuple

template <typename... Types>

ETL_NODISCARD

ETL_CONSTEXPR14

auto to_std(const etl::tuple<Types...>& etl_tuple)

Converts an etl::tuple to a std::tuple.

Enabled when STL is available.

template <typename... Types>

ETL_NODISCARD

ETL_CONSTEXPR14

auto to_std(etl::tuple<Types...>&& etl_tuple)

Converts an etl::tuple to a std::tuple.

Enabled when STL is available.

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Convert an std::tuple to a etl::tuple

template <typename... Types>

ETL_NODISCARD

ETL_CONSTEXPR14

auto to_etl(const std::tuple<Types...>& std_tuple)

Converts a std::tuple to an etl::tuple.

Enabled when STL is available.

template <typename... Types>

ETL_NODISCARD

ETL_CONSTEXPR14

auto to_etl(std::tuple<Types...>&& std_tuple)

Converts a std::tuple to an etl::tuple.

Enabled when STL is available.

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Create a tuple from selected elements of another

template <typename Tuple, size_t... Indices>

ETL_NODISCARD

ETL_CONSTEXPR14

auto select_from_tuple(Tuple&& tuple, etl::index_sequence<Indices...>)

Creates a new tuple by selecting elements from another, given a run time index sequence.

Static asserts if the number of indices does not match the tuple size.

template <size_t... Indices, typename Tuple>

ETL_NODISCARD

ETL_CONSTEXPR14

auto select_from_tuple(Tuple&& tuple)

Creates a new tuple by selecting elements from another, given a template parameter index sequence.

Static asserts if the number of indices does not match the tuple size.

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Non-member functions

template <size_t Index, typename... Types>

ETL_CONSTEXPR14

etl::tuple_element_t<Index, etl::tuple<Types...>>& get(tuple<Types...>&);

template <size_t Index, typename... Types>

ETL_CONSTEXPR14

etl::tuple_element_t<Index, etl::tuple<Types...>>&& get(tuple<Types...>&&);

template <size_t Index, typename... Types>

ETL_CONSTEXPR14

const etl::tuple_element_t<Index, etl::tuple<Types...>>& get(const tuple<Types...>&);

template <size_t Index, typename... Types>

ETL_CONSTEXPR14

const etl::tuple_element_t<Index, etl::tuple<Types...>>&& get(const tuple<Types...>&&);

template <typename T, typename... Types>

ETL_CONSTEXPR14

T& get(tuple<Types...>&);

template <typename T, typename... Types>

ETL_CONSTEXPR14

T&& get(tuple<Types...>&&);

template <typename T, typename... Types>

ETL_CONSTEXPR14

const T& get(const tuple<Types...>&);

template <typename T, typename... Types>

ETL_CONSTEXPR14

const T&& get(const tuple<Types...>&&);

tuple.h