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

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< cpp‎ | utility‎ | expected
 
 
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constexpr const E& error() const& noexcept;
(1) (since C++23)
constexpr E& error() & noexcept;
(2) (since C++23)
constexpr const E&& error() const&& noexcept;
(3) (since C++23)
constexpr E&& error() && noexcept;
(4) (since C++23)

Accesses the unexpected value contained in *this.

The behavior is undefined if this->has_value() is true.

Contents

[edit] Parameters

(none)

[edit] Return value

Reference to the unexpected value contained in *this.

[edit] Example

[edit] See also

accesses the expected value
(public member function) [edit]
(C++23)
returns the expected value
(public member function) [edit]
checks whether the object contains an expected value
(public member function) [edit]