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std::expected<T,E>::expected

From cppreference.com
< cpp‎ | utility‎ | expected
 
C++
 
Utilities library
General utilities
Relational operators (deprecated in C++20)
 
std::expected
 
Main template
constexpr expected();
 (1) (since C++23)
constexpr expected( const expected& other );
 (2) (since C++23)
constexpr expected( expected&& other ) noexcept(/* see below */);
 (3) (since C++23)
template< class U, class G >
constexpr expected( const expected<U, G>& other );
 (4) (since C++23)
(conditionally explicit)
template< class U, class G >
constexpr expected( expected<U, G>&& other );
 (5) (since C++23)
(conditionally explicit)
template< class U = std::remove_cv_t<T> >
constexpr explicit(!std::is_convertible_v<U, T>) expected( U&& v );
 (6) (since C++23)
template< class G >

constexpr explicit(!std::is_convertible_v<const G&, E>)

    expected( const std::unexpected<G>& e );
 (7) (since C++23)
template< class G >

constexpr explicit(!std::is_convertible_v<G, E>)

    expected( std::unexpected<G>&& e );
 (8) (since C++23)
template< class... Args >
constexpr explicit expected( std::in_place_t, Args&&... args );
 (9) (since C++23)
template< class U, class... Args >

constexpr explicit
    expected( std::in_place_t,

              std::initializer_list<U> il, Args&&... args );
 (10) (since C++23)
template< class... Args >
constexpr explicit expected( std::unexpect_t, Args&&... args );
 (11) (since C++23)
template< class U, class... Args >

constexpr explicit
    expected( std::unexpect_t,

              std::initializer_list<U> il, Args&&... args );
 (12) (since C++23)
void partial specialization
constexpr expected();
 (13) (since C++23)
constexpr expected( const expected& other );
 (14) (since C++23)
constexpr expected( expected&& other )
    noexcept(std::is_nothrow_move_constructible_v<E>);
 (15) (since C++23)
template< class U, class G >

constexpr explicit(!std::is_convertible_v<const G&, E>)

    expected( const expected<U, G>& other );
 (16) (since C++23)
template< class U, class G >

constexpr explicit(!std::is_convertible_v<G, E>)

    expected( expected<U, G>&& other );
 (17) (since C++23)
template< class G >

constexpr explicit(!std::is_convertible_v<const G&, E>)

    expected( const std::unexpected<G>& e );
 (18) (since C++23)
template< class G >

constexpr explicit(!std::is_convertible_v<G, E>)

    expected( std::unexpected<G>&& e );
 (19) (since C++23)
constexpr explicit expected( std::in_place_t );
 (20) (since C++23)
template< class... Args >
constexpr explicit expected( std::unexpect_t, Args&&... args );
 (21) (since C++23)
template< class U, class... Args >

constexpr explicit
    expected( std::unexpect_t,

              std::initializer_list<U> il, Args&&... args );
 (22) (since C++23)

Constructs a new expected object.

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