function_traits

Allows the traits of functions to be determined.

template <typename T>

struct function_traits;

template <typename TReturn, typename... TArgs>

struct function_traits<TReturn(*)(TArgs...)>

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Member types

function_type

The signature of the function.

TReturn(TArgs...)

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return_type

The return type.

TReturn

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object_type

The object type, if a member function.

Otherwise void.

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argument_types

An etl::type_list of the arguments.

etl::type_list<TArgs...>

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is_function

true if a free or static member function.

bool

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is_member_function

true if a member function.

bool

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is_const

true if a const member function.

bool

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argument_count

The number of arguments.

size_t

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Example

int free_int(int i, int j);

class Object

{

public:

int member_int(int i, int j);

int member_int_const(int i, int j) const;

static void member_static(int i, int j);

};

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using traits1 = etl::function_traits<decltype(&free_int)>;

function_type int(int, int)

return_type int

object_type void

argument_types etl::type_list<int, int>

is_function true

is_member_function false

is_const false

argument_count 2

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using traits2 = etl::function_traits<decltype(&Object::member_int)>;

function_type int(int, int)

return_type int

object_type Object

argument_types etl::type_list<int, int>

is_function false

is_member_function true

is_const false

argument_count 2

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using traits3 = etl::function_traits<decltype(&Object::member_int_const)>;

function_type int(int, int) const

return_type int

object_type Object

argument_types etl::type_list<int, int>

is_function false

is_member_function true

is_const true

argument_count 2

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using traits4 = etl::function_traits<decltype(&Object::member_static)>;

function_type void(int, int)

return_type void

object_type void

argument_types etl::type_list<int, int>

is_function true

is_member_function false

is_const false

argument_count 2

function_traits.h