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

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std::expected

Member functions
expected::expected
expected::~expected
expected::operator=
Observers
expected::operator->expected::operator*
expected::operator boolexpected::has_value
expected::value
expected::error
expected::value_or
expected::error_or
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expected::and_then
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expected::transform
expected::transform_error
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expected::emplace
expected::swap
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operator==(std::expected)
swap(std::expected)
Helper classes
unexpected
bad_expected_access
unexpect_tunexpect

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template<class G= E> constexpr E error_or( G&& default_value)const&;	(1)	(since C++23)
template<class G= E> constexpr E error_or( G&& default_value)&&;	(2)	(since C++23)

Returns the unexpected value if it exists, otherwise returnsdefault_value.

1) Ifstd::is_copy_constructible_v<E> orstd::is_convertible_v<G, E> isfalse, the program is ill-formed.

2) Ifstd::is_move_constructible_v<E> orstd::is_convertible_v<G, E> isfalse, the program is ill-formed.

[edit]Parameters

default_value	-	the value to use in case*this does not contain an unexpected value
Type requirements

[edit]Return value

1)has_value()?std::forward<G>(default_value): error()

2)has_value()?std::forward<G>(default_value): std::move(error())

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

error	returns the unexpected value (public member function)[edit]
value_or	returns the expected value if present, another value otherwise (public member function)[edit]