type_lookup

Type Lookup

Compile time mapping of id to type, type to id and type to type.

This file is generated from type_lookup_generator.h and can be created by running generate_type_lookup.bat.

For a less complex solution for simple id to type lookup, see etl::type_select.

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type_id_pair

Support structure for type_id_lookup.

etl::type_id_pair<typename T, size_t ID>

Defines:

type The type.

ID The id associated with the type.

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type_type_pair

Support structure for type_type_lookup.

etl::type_type_pair<typename T1, typename T2>

Defines:

type1 The indexing type.

type2 The associated type.

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type_id_lookup

Creates a class for compile time id to type and type to id mappings.

etl::type_id_lookup<typename T1, ...>

The number of types that can be handled is determined by the generator.

Each template parameter is a type_id_pair.

The class contains two nested templates

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type_from_id

Gets the type from the id.

type_from_id<size_t ID>

Defines:

type The associated type.

C++14 and above

template <int ID>

using type_from_id_t = typename type_from_id<ID>::type;

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id_from_type

Gets the id from the type.

id_from_type<typename T>

Defines:

ID The associated id.

C++ 17 and above

template <typename T>

constexpr size_t id_from_type_v = id_from_type<T>::value;

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Static functions

Gets the id from the type.

template <typename T>

static unsigned int get_id_from_type(const T&)

template <typename T>

static unsigned int get_id_from_type()

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type_type_lookup

Creates a class for compile time type to type mapping.

etl::type_id_lookup<typename T1, ...>

The number of types that can be handled is determined by the generator.

Each template parameter is a type_id_pair.

The class contains one nested template.

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type_from_type

type_from_type<typename T>

Defines:

type The associated type.

C++14 and above

template <typename T>

using type_from_type_t = typename type_from_type<T>::type;

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nth_type

Gets the nth type in a variadic type list.

template <size_t N, typename... TTypes>

struct nth_type

Defines member type as the nth type in the variadic type list.

template <size_t N, typename... TTypes>

using nth_type_t = typename nth_type<N, TTypes...>::type;

Type alias defined as the nth type in the variadic type list.

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Examples

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type_id_lookup

enum

{

INT32 = 32,

STRING = 1,

UINT8 = 8,

OTHER = 0

};

typedef etl::type_id_pair<int32_t, INT32> TypeIdInt32;

typedef etl::type_id_pair<uint8_t, UINT8> TypeIdUint8;

typedef etl::type_id_pair<std::string, STRING> TypeIdString;

// Type from Id / Id from Type.

typedef etl::type_id_lookup<TypeIdInt32, TypeIdString, TypeIdUint8> TypeIdLookup;

// int32_t

typename TypeIdLookup::type_from_id_t<INT32>

// uint8_t

typename TypeIdLookup::type_from_id_t<UINT8>

// std::string

typename TypeIdLookup::type_from_id_t<STRING>

// Compile error

typename TypeIdLookup::type_from_id_t<OTHER>

// INT32

TypeIdLookup::id_from_type_v<int32_t>

// UINT8

TypeIdLookup::id_from_type_v<uint8_t>

// STRING

TypeIdLookup::id_from_type_v<std::string>

// Compile error

TypeIdLookup::id_from_type_v<double>

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type_type_lookup

// Get the next larger type.

typedef etl::type_type_pair<int16_t, int32_t> TypeInt16;

typedef etl::type_type_pair<uint8_t, uint16_t> TypeUint8;

typedef etl::type_type_pair<float, double> TypeFloat;

// Type from Type.

etl::type_type_lookup<TypeInt16, TypeUint8, TypeFloat> TypeTypeLookup;

// int32_t

typename TypeTypeLookup::type_from_type_t<int16_t>

// uint16_t

typename TypeTypeLookup::type_from_type_t<uint8_t>

// double

typename TypeTypeLookup::type_from_type_t<float>

// Compile error

typename TypeTypeLookup::type_from_type_t<int32_t>

type_lookup.h