cvw::unexpected

Wrapper type for constructing expected objects in error state. More...

#include <expected.hpp>

Public Functions

	Name
	unexpected() =delete Deleted default constructor.
template <typenameErr =E&gt; constexpr	unexpected(Err && e) Constructs unexpected from an error value.
template <typename... Args&gt; constexpr	unexpected(std::in_place_t , Args &&... args) Constructs unexpected in-place with arguments.
template <typenameU ,typename... Args&gt; constexpr	unexpected(std::in_place_t , std::initializer_list<U> il, Args &&... args) Constructs unexpected in-place with initializer list.
constexprconstE &	error() const Returns const reference to the error.
constexprE &	error() Returns reference to the error.
constexprconstE &&	error() const Returns const rvalue reference to the error.
constexprE &&	error() Returns rvalue reference to the error.
void	swap(unexpected & other) Swaps the error with another unexpected.

Friends

	Name
constexprbool	operator==(constunexpected & a, constunexpected<E2> & b) Compares two unexpected objects for equality.

Detailed Description

template <typenameE>
class cvw::unexpected;

Wrapper type for constructing expected objects in error state.

Template Parameters:

• E Error type to wrap.

Public Functions Documentation

function unexpected

unexpected() =delete

Deleted default constructor.

function unexpected

template <typenameErr  =E>
inline explicit constexpr unexpected(
    Err && e
)

Constructs unexpected from an error value.

Parameters:

• e Error value to wrap.

Template Parameters:

• Err Forwarded error type.

function unexpected

template <typename... Args>
inline explicit constexpr unexpected(
    std::in_place_t ,
    Args &&... args
)

Constructs unexpected in-place with arguments.

Parameters:

• args Arguments to forward to E constructor.

Template Parameters:

• Args Constructor argument types.

function unexpected

template <typenameU ,
typename... Args>
inline explicit constexpr unexpected(
    std::in_place_t ,
    std::initializer_list< U > il,
    Args &&... args
)

Constructs unexpected in-place with initializer list.

Parameters:

• il Initializer list.
• args Additional arguments.

Template Parameters:

• U Element type of initializer list.
• Args Constructor argument types.

function error

inline constexprconstE & error() const

Returns const reference to the error.

Exceptions:

• None.

Return: Const reference to the error.

function error

inline constexprE & error()

Returns reference to the error.

Exceptions:

• None.

Return: Reference to the error.

function error

inline constexprconstE && error() const

Returns const rvalue reference to the error.

Exceptions:

• None.

Return: Const rvalue reference to the error.

function error

inline constexprE && error()

Returns rvalue reference to the error.

Exceptions:

• None.

Return: Rvalue reference to the error.

function swap

inline void swap(
    unexpected & other
)

Swaps the error with another unexpected.

Parameters:

• other Other unexpected to swap with.

Exceptions:

• None if E is nothrow swappable.

Since: 0.1

Note: None.

Warning: None.

Friends

friend operator==

friend constexprbool operator==(
    constunexpected & a,

    constunexpected<E2> & b
);

Compares two unexpected objects for equality.

Parameters:

• a First unexpected.
• b Second unexpected.

Exceptions:

• None.

Template Parameters:

• E2 Error type of the other unexpected.

Return: true if errors are equal, false otherwise.

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Updated on 2026-05-17 at 13:22:38 +0000