opcua::Span< T > Class Template Reference

#include <span.hpp>

Detailed Description

template<typename T>
class opcua::Span< T >

View to a contiguous sequence of objects, similar to std::span in C++20.

Spans are used to pass and return open62541 arrays without copy and to use them with the standard library algorithms. The view just holds two members: the pointer to T and the size, so it's lightweight and trivially copyable.

Template Parameters

T	Type of the array object, use const T for an immutable view

See also

https://en.cppreference.com/w/cpp/container/span

Examples

custom_datatypes/client_custom_datatypes.cpp, custom_datatypes/server_custom_datatypes.cpp, events/client_eventfilter.cpp, events/server_events.cpp, method/server_method.cpp, method/server_method_async.cpp, and typeconversion.cpp.

Definition at line 29 of file span.hpp.

Public Types
using	element_type = T
using	value_type = std::remove_cv_t< T >
using	size_type = size_t
using	difference_type = std::ptrdiff_t
using	pointer = T *
using	const_pointer = const T *
using	reference = T &
using	const_reference = const T &
using	iterator = pointer
using	const_iterator = const_pointer
using	reverse_iterator = std::reverse_iterator< iterator >
using	const_reverse_iterator = std::reverse_iterator< const_iterator >

Public Member Functions
constexpr	Span () noexcept=default
constexpr	Span (T *data, size_t size) noexcept
template<typename Container , typename = EnableIfHasSizeAndData<Container>>
constexpr	Span (Container &container) noexcept
template<typename Container , typename = EnableIfHasSizeAndData<Container>>
constexpr	Span (const Container &container) noexcept
constexpr	Span (std::initializer_list< value_type > values) noexcept
constexpr void	swap (Span &other) noexcept
constexpr size_t	size () const noexcept
constexpr bool	empty () const noexcept
constexpr pointer	data () const noexcept
constexpr reference	operator[] (size_t index) const noexcept
constexpr reference	at (size_t index) const
constexpr reference	front () const noexcept
constexpr reference	back () const noexcept
constexpr iterator	begin () const noexcept
constexpr iterator	end () const noexcept
constexpr const_iterator	cbegin () const noexcept
constexpr const_iterator	cend () const noexcept
constexpr reverse_iterator	rbegin () const noexcept
constexpr reverse_iterator	rend () const noexcept
constexpr const_reverse_iterator	crbegin () const noexcept
constexpr const_reverse_iterator	crend () const noexcept
constexpr Span	subview (size_t offset, size_t count=(std::numeric_limits< std::size_t >::max)()) const noexcept
constexpr Span	first (size_t count) const noexcept
constexpr Span	last (size_t count) const noexcept

Related Symbols
(Note that these are not member symbols.)
template<typename Container >
	Span (Container &) -> Span< typename Container::value_type >
template<typename Container >
	Span (const Container &) -> Span< const typename Container::value_type >
template<typename T , typename U , typename = detail::EnableIfEqualityComparable<T, U>>
constexpr bool	operator== (Span< T > lhs, Span< U > rhs)
template<typename T , typename U , typename = detail::EnableIfEqualityComparable<T, U>>
constexpr bool	operator!= (Span< T > lhs, Span< U > rhs)

Member Typedef Documentation

const_iterator

template<typename T >

using opcua::Span< T >::const_iterator = const_pointer

Definition at line 48 of file span.hpp.

const_pointer

template<typename T >

using opcua::Span< T >::const_pointer = const T*

Definition at line 44 of file span.hpp.

const_reference

template<typename T >

using opcua::Span< T >::const_reference = const T&

Definition at line 46 of file span.hpp.

const_reverse_iterator

template<typename T >

using opcua::Span< T >::const_reverse_iterator = std::reverse_iterator<const_iterator>

Definition at line 50 of file span.hpp.

difference_type

template<typename T >

using opcua::Span< T >::difference_type = std::ptrdiff_t

Definition at line 42 of file span.hpp.

element_type

template<typename T >

using opcua::Span< T >::element_type = T

Definition at line 39 of file span.hpp.

iterator

template<typename T >

using opcua::Span< T >::iterator = pointer

Definition at line 47 of file span.hpp.

pointer

template<typename T >

using opcua::Span< T >::pointer = T*

Definition at line 43 of file span.hpp.

reference

template<typename T >

using opcua::Span< T >::reference = T&

Definition at line 45 of file span.hpp.

reverse_iterator

template<typename T >

using opcua::Span< T >::reverse_iterator = std::reverse_iterator<iterator>

Definition at line 49 of file span.hpp.

size_type

template<typename T >

using opcua::Span< T >::size_type = size_t

Definition at line 41 of file span.hpp.

value_type

template<typename T >

using opcua::Span< T >::value_type = std::remove_cv_t<T>

Definition at line 40 of file span.hpp.

Constructor & Destructor Documentation

Span() [1/5]

template<typename T >

constexpr opcua::Span< T >::Span ( )

constexprdefaultnoexcept

Span() [2/5]

template<typename T >

constexpr opcua::Span< T >::Span ( T *  data, size_t  size  )

inlineconstexprnoexcept

Definition at line 55 of file span.hpp.

Span() [3/5]

template<typename T >

template<typename Container , typename = EnableIfHasSizeAndData<Container>>

constexpr opcua::Span< T >::Span ( Container &  container )

inlineconstexprnoexcept

Implicit constructor from a container like std::array or std::vector.

Definition at line 63 of file span.hpp.

Span() [4/5]

template<typename T >

template<typename Container , typename = EnableIfHasSizeAndData<Container>>

constexpr opcua::Span< T >::Span ( const Container &  container )

inlineconstexprnoexcept

Implicit constructor from a container like std::array or std::vector (const).

Definition at line 70 of file span.hpp.

Span() [5/5]

template<typename T >

constexpr opcua::Span< T >::Span ( std::initializer_list< value_type >  values )

inlineconstexprnoexcept

Implicit constructor from an initializer list.

Only safe to use if std::initializer_list itself outlives the Span:

void takeView(Span<const int> values);
// ok
takeView({1, 2, 3});
// not ok
Span<const int> values = {1, 2, 3};
takeView(values);

Definition at line 86 of file span.hpp.

Member Function Documentation

at()

template<typename T >

constexpr reference opcua::Span< T >::at ( size_t  index ) const

inlineconstexpr

Access element by index with bounds checking.

Exceptions

std::out_of_range

If `index` >= size()

Examples

events/client_eventfilter.cpp, events/server_events.cpp, method/server_method.cpp, and method/server_method_async.cpp.

Definition at line 114 of file span.hpp.

back()

template<typename T >

constexpr reference opcua::Span< T >::back ( ) const

inlineconstexprnoexcept

Definition at line 126 of file span.hpp.

begin()

template<typename T >

constexpr iterator opcua::Span< T >::begin ( ) const

inlineconstexprnoexcept

Definition at line 131 of file span.hpp.

Referenced by opcua::ByteString::ByteString(), opcua::Span< T >::operator==(), and opcua::Span< T >::rend().

cbegin()

template<typename T >

constexpr const_iterator opcua::Span< T >::cbegin ( ) const

inlineconstexprnoexcept

Definition at line 139 of file span.hpp.

Referenced by opcua::Span< T >::crend().

cend()

template<typename T >

constexpr const_iterator opcua::Span< T >::cend ( ) const

inlineconstexprnoexcept

Definition at line 143 of file span.hpp.

Referenced by opcua::Span< T >::crbegin().

crbegin()

template<typename T >

constexpr const_reverse_iterator opcua::Span< T >::crbegin ( ) const

inlineconstexprnoexcept

Definition at line 155 of file span.hpp.

crend()

template<typename T >

constexpr const_reverse_iterator opcua::Span< T >::crend ( ) const

inlineconstexprnoexcept

Definition at line 159 of file span.hpp.

data()

template<typename T >

constexpr pointer opcua::Span< T >::data ( ) const

inlineconstexprnoexcept

Examples

typeconversion.cpp.

Definition at line 102 of file span.hpp.

Referenced by opcua::Span< T >::at(), opcua::Span< T >::back(), opcua::Span< T >::begin(), opcua::Span< T >::cbegin(), opcua::Span< T >::cend(), opcua::Span< T >::end(), opcua::Span< T >::first(), opcua::Span< T >::front(), opcua::Span< T >::last(), opcua::Span< T >::operator[](), and opcua::Span< T >::subview().

empty()

template<typename T >

constexpr bool opcua::Span< T >::empty ( ) const

inlineconstexprnoexcept

Definition at line 98 of file span.hpp.

Referenced by opcua::Span< T >::back(), and opcua::Span< T >::front().

end()

template<typename T >

constexpr iterator opcua::Span< T >::end ( ) const

inlineconstexprnoexcept

Definition at line 135 of file span.hpp.

Referenced by opcua::ByteString::ByteString(), opcua::Span< T >::operator==(), and opcua::Span< T >::rbegin().

first()

template<typename T >

constexpr Span opcua::Span< T >::first ( size_t  count ) const

inlineconstexprnoexcept

Obtain a view over the first count elements of this Span.

Definition at line 177 of file span.hpp.

front()

template<typename T >

constexpr reference opcua::Span< T >::front ( ) const

inlineconstexprnoexcept

Definition at line 121 of file span.hpp.

last()

template<typename T >

constexpr Span opcua::Span< T >::last ( size_t  count ) const

inlineconstexprnoexcept

Obtain a view over the last count elements of this Span.

Definition at line 185 of file span.hpp.

operator[]()

template<typename T >

constexpr reference opcua::Span< T >::operator[] ( size_t  index ) const

inlineconstexprnoexcept

Access element by index.

Definition at line 107 of file span.hpp.

rbegin()

template<typename T >

constexpr reverse_iterator opcua::Span< T >::rbegin ( ) const

inlineconstexprnoexcept

Definition at line 147 of file span.hpp.

rend()

template<typename T >

constexpr reverse_iterator opcua::Span< T >::rend ( ) const

inlineconstexprnoexcept

Definition at line 151 of file span.hpp.

size()

template<typename T >

constexpr size_t opcua::Span< T >::size ( ) const

inlineconstexprnoexcept

Definition at line 94 of file span.hpp.

Referenced by opcua::ua::AddNodesRequest::AddNodesRequest(), opcua::ua::AddReferencesRequest::AddReferencesRequest(), opcua::ua::ApplicationDescription::ApplicationDescription(), opcua::Span< T >::at(), opcua::ua::AxisInformation::AxisInformation(), opcua::Span< T >::back(), opcua::ua::BrowseNextRequest::BrowseNextRequest(), opcua::ua::BrowseRequest::BrowseRequest(), opcua::ua::CallMethodRequest::CallMethodRequest(), opcua::ua::CallRequest::CallRequest(), opcua::Span< T >::cend(), opcua::ua::CreateMonitoredItemsRequest::CreateMonitoredItemsRequest(), opcua::ua::DeleteMonitoredItemsRequest::DeleteMonitoredItemsRequest(), opcua::ua::DeleteNodesRequest::DeleteNodesRequest(), opcua::ua::DeleteReferencesRequest::DeleteReferencesRequest(), opcua::ua::DeleteSubscriptionsRequest::DeleteSubscriptionsRequest(), opcua::Span< T >::empty(), opcua::Span< T >::end(), opcua::ua::EnumDefinition::EnumDefinition(), opcua::ua::EventFilter::EventFilter(), opcua::Span< T >::first(), opcua::Span< T >::last(), opcua::ua::ModifyMonitoredItemsRequest::ModifyMonitoredItemsRequest(), opcua::Span< T >::operator[](), opcua::ua::ReadRequest::ReadRequest(), opcua::ua::RegisterNodesRequest::RegisterNodesRequest(), opcua::ua::RelativePath::RelativePath(), opcua::ua::SetMonitoringModeRequest::SetMonitoringModeRequest(), opcua::ua::SetPublishingModeRequest::SetPublishingModeRequest(), opcua::ua::SetTriggeringRequest::SetTriggeringRequest(), opcua::Span< T >::Span(), opcua::Span< T >::subview(), opcua::ua::TranslateBrowsePathsToNodeIdsRequest::TranslateBrowsePathsToNodeIdsRequest(), opcua::ua::UnregisterNodesRequest::UnregisterNodesRequest(), and opcua::ua::WriteRequest::WriteRequest().

subview()

template<typename T >

constexpr Span opcua::Span< T >::subview ( size_t  offset, size_t  count = (std::numeric_limits<std::size_t>::max)()  ) const

inlineconstexprnoexcept

Obtain a view over count elements of this Span starting at offset offset.

Definition at line 164 of file span.hpp.

swap()

template<typename T >

constexpr void opcua::Span< T >::swap ( Span< T > &  other )

inlineconstexprnoexcept

Definition at line 89 of file span.hpp.

Friends And Related Symbol Documentation

operator!=()

template<typename T , typename U , typename = detail::EnableIfEqualityComparable<T, U>>

constexpr bool operator!= ( Span< T >  lhs, Span< U >  rhs  )

related

Definition at line 238 of file span.hpp.

operator==()

template<typename T , typename U , typename = detail::EnableIfEqualityComparable<T, U>>

constexpr bool operator== ( Span< T >  lhs, Span< U >  rhs  )

related

Definition at line 232 of file span.hpp.

Span() [1/2]

template<typename Container >

Span ( const Container &  ) -> Span< const typename Container::value_type >

related

Span() [2/2]

template<typename Container >

Span ( Container &  ) -> Span< typename Container::value_type >

related