caf::expected< T > Class Template Reference

Represents the result of a computation which can either complete successfully with an instance of type T or fail with an error. More...

#include <expected.hpp>

Public Types
using	value_type = T

Public Member Functions
template<class U >
	expected (U x, typename std::enable_if< std::is_convertible< U, T >::value >::type *=nullptr)
	expected (T &&x) noexcept(nothrow_move)
	expected (const T &x) noexcept(nothrow_copy)
	expected (caf::error e) noexcept
	expected (const expected &other) noexcept(nothrow_copy)
template<class Enum , class = std::enable_if_t<is_error_code_enum_v<Enum>>>
	expected (Enum code)
	expected (expected &&other) noexcept(nothrow_move)
expected &	operator= (const expected &other) noexcept(nothrow_copy)
expected &	operator= (expected &&other) noexcept(nothrow_move)
expected &	operator= (const T &x) noexcept(nothrow_copy)
expected &	operator= (T &&x) noexcept(nothrow_move)
template<class U >
std::enable_if< std::is_convertible< U, T >::value, expected & >::type	operator= (U x)
expected &	operator= (caf::error e) noexcept
template<class Enum , class = std::enable_if_t<is_error_code_enum_v<Enum>>>
expected &	operator= (Enum code)
T &	value () noexcept
	Returns the contained value.
T &	operator* () noexcept
	Returns the contained value.
T *	operator-> () noexcept
	Returns the contained value.
caf::error &	error () noexcept
	Returns the contained error.
const T &	cvalue () const noexcept
	Returns the contained value.
const T &	value () const noexcept
	Returns the contained value.
const T &	operator* () const noexcept
	Returns the contained value.
const T *	operator-> () const noexcept
	Returns the contained value.
	operator bool () const noexcept
	Returns true if the object holds a value (is engaged).
bool	engaged () const noexcept
	Returns true if the object holds a value (is engaged).
const caf::error &	cerror () const noexcept
	Returns the contained error.
const caf::error &	error () const noexcept
	Returns the contained error.

Static Public Attributes
static constexpr bool	nothrow_move
	Stores whether move construct and move assign never throw.
static constexpr bool	nothrow_copy
	Stores whether copy construct and copy assign never throw.

Related Functions
(Note that these are not member functions.)
template<class T >
auto	operator== (const expected< T > &x, const expected< T > &y) -> decltype(*x==*y)
template<class T , class U >
auto	operator== (const expected< T > &x, const U &y) -> decltype(*x==y)
template<class T , class U >
auto	operator== (const T &x, const expected< U > &y) -> decltype(x==*y)
template<class T >
bool	operator== (const expected< T > &x, const error &y)
template<class T >
bool	operator== (const error &x, const expected< T > &y)
template<class T , class Enum >
std::enable_if_t< is_error_code_enum_v< Enum >, bool >	operator== (const expected< T > &x, Enum y)
template<class T , class Enum >
std::enable_if_t< is_error_code_enum_v< Enum >, bool >	operator== (Enum x, const expected< T > &y)
template<class T >
auto	operator!= (const expected< T > &x, const expected< T > &y) -> decltype(*x==*y)
template<class T , class U >
auto	operator!= (const expected< T > &x, const U &y) -> decltype(*x==y)
template<class T , class U >
auto	operator!= (const T &x, const expected< U > &y) -> decltype(x==*y)
template<class T >
bool	operator!= (const expected< T > &x, const error &y)
template<class T >
bool	operator!= (const error &x, const expected< T > &y)
template<class T , class Enum >
std::enable_if_t< is_error_code_enum_v< Enum >, bool >	operator!= (const expected< T > &x, Enum y)
template<class T , class Enum >
std::enable_if_t< is_error_code_enum_v< Enum >, bool >	operator!= (Enum x, const expected< T > &y)
bool	operator== (const expected< void > &x, const expected< void > &y)
bool	operator!= (const expected< void > &x, const expected< void > &y)

Detailed Description

template<typename T>
class caf::expected< T >

Represents the result of a computation which can either complete successfully with an instance of type T or fail with an error.

Template Parameters

T	The type of the result.

Member Function Documentation

cerror()

template<typename T >

const caf::error & caf::expected< T >::cerror ( ) const

noexcept

Returns the contained error.

Precondition

engaged() == false.

cvalue()

template<typename T >

const T & caf::expected< T >::cvalue ( ) const

noexcept

Returns the contained value.

Precondition

engaged() == true.

error() [1/2]

template<typename T >

const caf::error & caf::expected< T >::error ( ) const

noexcept

Returns the contained error.

Precondition

engaged() == false.

error() [2/2]

template<typename T >

caf::error & caf::expected< T >::error ( )

noexcept

Returns the contained error.

Precondition

engaged() == false.

operator bool()

template<typename T >

caf::expected< T >::operator bool ( ) const

explicitnoexcept

Returns true if the object holds a value (is engaged).

operator*() [1/2]

template<typename T >

const T & caf::expected< T >::operator* ( ) const

noexcept

Returns the contained value.

Precondition

engaged() == true.

operator*() [2/2]

template<typename T >

T & caf::expected< T >::operator* ( )

noexcept

Returns the contained value.

Precondition

engaged() == true.

operator->() [1/2]

template<typename T >

const T * caf::expected< T >::operator-> ( ) const

noexcept

Returns the contained value.

Precondition

engaged() == true.

operator->() [2/2]

template<typename T >

T * caf::expected< T >::operator-> ( )

noexcept

Returns the contained value.

Precondition

engaged() == true.

value() [1/2]

template<typename T >

const T & caf::expected< T >::value ( ) const

noexcept

Returns the contained value.

Precondition

engaged() == true.

value() [2/2]

template<typename T >

T & caf::expected< T >::value ( )

noexcept

Returns the contained value.

Precondition

engaged() == true.

Member Data Documentation

nothrow_copy

template<typename T >

constexpr bool caf::expected< T >::nothrow_copy

staticconstexpr

Initial value:

= std::is_nothrow_copy_constructible<T>::value
      && std::is_nothrow_copy_assignable<T>::value

Stores whether copy construct and copy assign never throw.

nothrow_move

template<typename T >

constexpr bool caf::expected< T >::nothrow_move

staticconstexpr

Initial value:

= std::is_nothrow_move_constructible<T>::value
      && std::is_nothrow_move_assignable<T>::value

Stores whether move construct and move assign never throw.

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

• libcaf_core/caf/expected.hpp