xentara::utils::windows::wmi::ResultSet Class Reference

A result set of a WMI query. More...

#include <xentara/utils/windows/wmi/ResultSet.hpp>

Public Types
using	value_type = Object
	The value type.
using	difference_type = std::ptrdiff_t
	Dummy type for non-existend difference type.
using	pointer = Object *
	A pointer to a value.
using	reference = Object &
	A reference to a value.
using	iterator_concept = std::input_iterator_tag
	The iterator concept.
using	iterator_category = iterator_concept
	The iterator category, for use in pre-C++20 code.

Public Member Functions
constexpr	ResultSet () noexcept=default
	Default constructor.
constexpr	ResultSet (std::default_sentinel_t) noexcept
	Constructor for a sentinel.
auto	singleObject () -> Object
	Returns the object contained in a result set containing exactly one object.
auto	operator== (const ResultSet &rhs) const noexcept
	Equality operator.
auto	operator== (std::default_sentinel_t) const noexcept
	Comparison with a sentinel.
auto	operator* () const noexcept -> const Object &
	Accesses the current object.
auto	operator* () noexcept -> Object &
	Accesses the current object.
auto	operator-> () const noexcept -> Object *
	Accesses the current object.
auto	operator++ () -> ResultSet &
	Fetches the next object in the result set.

Related Symbols
(Note that these are not member symbols.)
auto	begin (ResultSet resultSet) -> ResultSet
	Gets an end iterator for a result set.
auto	end (ResultSet) -> std::default_sentinel_t
	Gets an end iterator for a result set.

Detailed Description

A result set of a WMI query.

This is an enumerator object that can be used to retreive all the objects in the result set one by one. Result sets are input iterators and can be used in algorithms that take an input iterator. Result sets also supply freestanding [begin()](xentara::utils::windows::wmi::begin(ResultSet)) and [end()](xentara::utils::windows::wmi::end(ResultSet)) functions, so they can be used in range-based for loops:

for (auto &&object : wmiNamespace.query("SELECT * FROM __Namespace"))
{
    ...
}

See also

Namespace::query()

Member Typedef Documentation

difference_type

using xentara::utils::windows::wmi::ResultSet::difference_type = std::ptrdiff_t

Dummy type for non-existend difference type.

iterator_category

using xentara::utils::windows::wmi::ResultSet::iterator_category = iterator_concept

The iterator category, for use in pre-C++20 code.

iterator_concept

using xentara::utils::windows::wmi::ResultSet::iterator_concept = std::input_iterator_tag

The iterator concept.

pointer

using xentara::utils::windows::wmi::ResultSet::pointer = Object *

A pointer to a value.

reference

using xentara::utils::windows::wmi::ResultSet::reference = Object &

A reference to a value.

value_type

using xentara::utils::windows::wmi::ResultSet::value_type = Object

The value type.

Constructor & Destructor Documentation

ResultSet() [1/2]

constexpr xentara::utils::windows::wmi::ResultSet::ResultSet ( )

constexprdefaultnoexcept

Default constructor.

This constructor constructs a result set that contains no objects.

Default constructed Result sets compare equal to exhaused result sets, so they can be used as sentinels in algorithms that require the iterator and sentinel to be of the same type.

ResultSet() [2/2]

constexpr xentara::utils::windows::wmi::ResultSet::ResultSet ( std::default_sentinel_t  )

constexprnoexcept

Constructor for a sentinel.

This constructor constructs an object that compares equal to exhaused result sets, so it can be used as a sentinel in algorithms that require the iterator and sentinel to be of the same type.

This constructor is identical to the default constructor.

Member Function Documentation

operator*() [1/2]

auto xentara::utils::windows::wmi::ResultSet::operator* ( ) const -> const Object &

noexcept

Accesses the current object.

Precondition

Must not be called on an exhaused result set

operator*() [2/2]

auto xentara::utils::windows::wmi::ResultSet::operator* ( ) -> Object &

noexcept

Accesses the current object.

Precondition

Must not be called on an exhaused result set

operator++()

auto xentara::utils::windows::wmi::ResultSet::operator++

(

)

-> ResultSet &

Fetches the next object in the result set.

Precondition

Must not be called on an exhaused result set

Exceptions

std::runtime_error

An error occurred trying to fetch the next object

operator->()

auto xentara::utils::windows::wmi::ResultSet::operator-> ( ) const -> Object *

noexcept

Accesses the current object.

Precondition

Must not be called on an exhaused result set

operator==() [1/2]

auto xentara::utils::windows::wmi::ResultSet::operator== ( const ResultSet &  rhs ) const

noexcept

Equality operator.

A result set only compares equal to itself, except exhaused result sets, that compare equal to all other exhaused result sets, including default constructed result sets. This allows using default constructed result sets as sentinels in algorithms that require the iterator and sentinel to be of the same type.

operator==() [2/2]

auto xentara::utils::windows::wmi::ResultSet::operator== ( std::default_sentinel_t  ) const

noexcept

Comparison with a sentinel.

Returns

Returns true if the result set is exhaused, or false if it contains a valid object.

singleObject()

auto xentara::utils::windows::wmi::ResultSet::singleObject

(

)

-> Object

Returns the object contained in a result set containing exactly one object.

Returns

The object

Exceptions

std::runtime_error

The result set is empty, or contains more than one object.

Friends And Related Symbol Documentation

begin()

auto begin ( ResultSet  resultSet ) -> ResultSet

related

Gets an end iterator for a result set.

This function enables the use of ResultSet in range-based for loops

Parameters

resultSet

The result set to iterate over

Returns

Returns a copy of the result set, since the result is its own iterator

end()

auto end ( ResultSet  ) -> std::default_sentinel_t

related

Gets an end iterator for a result set.

This function enables the use of ResultSet in range-based for loops

Returns

The global default sentinel