std::unexpect_t, std::unexpect

 

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Utilities library

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std::expected

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expected::expected (C++23)

expected::~expected (C++23)

expected::operator= (C++23)

Observers

expected::operator->expected::operator* (C++23)(C++23)

expected::operator boolexpected::has_value (C++23)(C++23)

expected::value (C++23)

expected::error (C++23)

expected::value_or (C++23)

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expected::and_then (C++23)

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expected::transform_error (C++23)

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expected::emplace (C++23)

expected::swap (C++23)

Non-member functions

operator== (C++23)

swap (C++23)

Helper classes

unexpected (C++23)

bad_expected_access (C++23)

unexpect_tunexpect (C++23)(C++23)

 

Defined in header <expected>
struct unexpect_t {     explicit unexpect_t() = default; };	(1)	(since C++23)
inline constexpr unexpect_t unexpect{};	(2)	(since C++23)

1) A tag type for in-place construction of an unexpected value in an std::expected object.

2) A constant of type const std::unexpect_t which is usually directly passed to a constructor of std::expected to construct an unexpected value.

Notes

Like other construction tag types, unexpect_t is a trivial, empty class with an explicit default constructor.

See also

(constructor) (C++23)

constructs the expected object (public member function)