The variant_sequential_view describes a class that refers to an sequence container (e.g: std::vector) inside a variant. More...

#include <variant_sequential_view.h>

Classes
class	const_iterator
	The variant_sequential_view::const_iterator allows iteration over an sequential container in a variant. More...

Public Member Functions
	variant_sequential_view ()
	Constructs an invalid variant_sequential_view object. More...

	variant_sequential_view (const variant_sequential_view &other)
	Constructs a copy of the given variant_sequential_view `other`. More...

	~variant_sequential_view () noexcept
	Destroys the variant_sequential_view. More...

const_iterator	begin () const
	Returns an iterator to the first element of the container. More...

void	clear ()
	Removes all elements from the container. More...

const_iterator	end () const
	Returns an iterator to the element following the last element of the container. More...

const_iterator	erase (const const_iterator &pos)
	Removes the element (if one exists) at the position `pos`. More...

std::size_t	get_rank () const noexcept
	Gets the rank (number of dimensions) of this sequential container. More...

type	get_rank_type (std::size_t index) const noexcept
	Gets the type of the given rank index. More...

std::size_t	get_size () const noexcept
	Returns the number of elements in the sequential container. More...

type	get_type () const noexcept
	Returns the type object of this sequential container. More...

variant	get_value (std::size_t index) const
	Returns the current value at index `index`. More...

type	get_value_type () const noexcept
	Returns the type object from the value of this sequential container. More...

const_iterator	insert (const const_iterator &pos, argument value)
	Insert a value into the container. More...

bool	is_dynamic () const noexcept
	Returns `true` if this sequential view is dynamic, otherwise `false`. More...

bool	is_empty () const noexcept
	Checks if the container has no elements. More...

bool	is_valid () const noexcept
	Returns true if this variant_sequential_view is valid, that means the object is holding some data. More...

	operator bool () const noexcept
	Convenience function to check if this variant_sequential_view is valid or not. More...

variant_sequential_view &	operator= (const variant_sequential_view &other) noexcept
	Assigns the value of the other variant_sequential_view to this variant_sequential_view. More...

bool	set_size (std::size_t size) const noexcept
	Sets the size of the sequential container. More...

bool	set_value (std::size_t index, argument arg)
	Set the content of the the argument `arg` at the specified index `index` into the underlying sequential container. More...

void	swap (variant_sequential_view &other) noexcept
	Swaps this variant_sequential_view with the other variant_sequential_view. More...

Detailed Description

The variant_sequential_view describes a class that refers to an sequence container (e.g: std::vector) inside a variant.

With an instance of that class you can set/get values of such container, without having access to the type declaration of the type or it's elements.

A variant_sequential_view can be created directly from a variant with its member function create_sequential_view().

Remarks: The instance of an variant_sequential_view is always valid as long as the referenced variant is valid, otherwise accessing a variant_sequential_view is undefined behaviour.

Meta Information

RTTR recognize whether a type is an sequential container or not with the help of the sequential_container_mapper class template. This call can access different container types via one common interface. At the moment there exist specializations for following types: std::vector<T>, std::array<T, std::size_t>, std::list<T>, std::deque<T>, std::initializer_list<T> and raw arrays

Copying and Assignment

A variant_sequential_view object can be copied and assigned, however each copy will reference the data of same underlying variant value.

Typical Usage

std::vector<int> my_vec = { 1, 2, 3, 4, 5};
variant var = my_vec; // copies data into variant
if (var.is_sequential_container())
{
    variant_sequential_view view = var.create_sequential_view();  // performs no copy of the underlying vector
    std::cout << view.get_size() << std::endl;  // prints: '5'
    for (const auto& item : view)
    {
        // remark that the value is stored inside a 'std::reference_wrapper', however there is an automatic conversion for wrapper classes implemented.
        std::cout << "data: " << item.to_string() << " ";
    }
}

Output:

1 2 3 4 5

See Also: variant, type::is_sequential_container()

Constructor & Destructor Documentation

rttr::variant_sequential_view::variant_sequential_view ( )

Constructs an invalid variant_sequential_view object.

See Also: is_valid()

rttr::variant_sequential_view::variant_sequential_view ( const variant_sequential_view & other )

Constructs a copy of the given variant_sequential_view other.

rttr::variant_sequential_view::~variant_sequential_view ( )

noexcept

Destroys the variant_sequential_view.

Remarks: The underlying data is not destroyed.

Member Function Documentation

const_iterator rttr::variant_sequential_view::begin ( ) const

Returns an iterator to the first element of the container.

See Also: end()

Returns: Iterator to the first element .

void rttr::variant_sequential_view::clear ( )

Removes all elements from the container.

Remarks: Invalidates all references, pointers, or iterators referring to contained elements.

const_iterator rttr::variant_sequential_view::end ( ) const

Returns an iterator to the element following the last element of the container.

See Also: begin()

Returns: Iterator to the element following the last element.

const_iterator rttr::variant_sequential_view::erase ( const const_iterator & pos )

Removes the element (if one exists) at the position pos.

Returns: Iterator following the last removed element.

std::size_t rttr::variant_sequential_view::get_rank ( ) const

noexcept

Gets the rank (number of dimensions) of this sequential container.

Take a look at following return values:

int[4] => 1
int[4][4] => 2
int[4][4][4] => 3
...

Returns: Returns the rank of the sequential container.

type rttr::variant_sequential_view::get_rank_type ( std::size_t index ) const

noexcept

Gets the type of the given rank index.

Take a look at following return value for an array of type: int[2][10]

get_rank_type(0) => int[2][10]
get_rank_type(1) => int[10]
get_rank_type(2) => int
get_rank_type(3) => INVALID

Returns: The rank type at the given dimension index.

std::size_t rttr::variant_sequential_view::get_size ( ) const

noexcept

Returns the number of elements in the sequential container.

Returns: The number of elements in the sequential container.

type rttr::variant_sequential_view::get_type ( ) const

noexcept

Returns the type object of this sequential container.

Remarks: When the view is not valid, this function will return an invalid type object.

Returns: Type of the sequential container.

variant rttr::variant_sequential_view::get_value ( std::size_t index ) const

Returns the current value at index index.

Returns: The data at the specified index index, wrapped inside a std::reference_wrapper<T>.

Remarks: Make sure the index is in a valid range, otherwise undefined behaviour may occurr. For MSVC 2013 and raw arrays, the address of the data is returned (because of a bug).

See Also: get_size()

type rttr::variant_sequential_view::get_value_type ( ) const

noexcept

Returns the type object from the value of this sequential container.

Remarks: When the view is not valid, this function will return an invalid type object.

Returns: Type from the value of the sequential container.

const_iterator rttr::variant_sequential_view::insert	(	const const_iterator &	pos,
		argument	value
	)

Insert a value into the container.

Returns: An iterator to the inserted element, otherwise an invalid iterator, when the insertion was not possible.

bool rttr::variant_sequential_view::is_dynamic ( ) const

noexcept

Returns true if this sequential view is dynamic, otherwise false.

   When an sequential view is dynamic, it is possible to change its \ref set_size "size",
   \ref clear its content or \ref insert and \ref erase values from it.

See Also: set_size(), insert(), erase(), clear()

Returns: A boolean flag which indicates whether this sequential container is dynamic or not.

bool rttr::variant_sequential_view::is_empty ( ) const

noexcept

Checks if the container has no elements.

Returns: true if container is empty, otherwise false.

bool rttr::variant_sequential_view::is_valid ( ) const

noexcept

Returns true if this variant_sequential_view is valid, that means the object is holding some data.

   When the variant_sequential_view doesn't hold any data it will return false.

Returns: True if this variant_sequential_view is valid, otherwise false.

rttr::variant_sequential_view::operator bool ( ) const

explicitnoexcept

Convenience function to check if this variant_sequential_view is valid or not.

See Also: is_valid()

Returns: True if this variant_sequential_view is valid, otherwise false.

variant_sequential_view& rttr::variant_sequential_view::operator= ( const variant_sequential_view & other )

noexcept

Assigns the value of the other variant_sequential_view to this variant_sequential_view.

Returns: A reference to the variant_sequential_view with the new data.

bool rttr::variant_sequential_view::set_size ( std::size_t size ) const

noexcept

Sets the size of the sequential container.

Returns: true, when the size of the container could be changed, otherwise false.

See Also: is_dynamic()

bool rttr::variant_sequential_view::set_value	(	std::size_t	index,
		argument	arg
	)

Set the content of the the argument arg at the specified index index into the underlying sequential container.

Returns: true if the value could be set, otherwise false.

void rttr::variant_sequential_view::swap ( variant_sequential_view & other )

noexcept

Swaps this variant_sequential_view with the other variant_sequential_view.

The documentation for this class was generated from the following file:

variant_sequential_view.h

Classes

Public Member Functions

Detailed Description

Meta Information

Copying and Assignment

Typical Usage

Constructor & Destructor Documentation

Member Function Documentation