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

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.

Parameters

(none)

Return value

Reference to the unexpected value contained in *this.

Example

See also

accesses the expected value
(public member function)
returns the expected value
(public member function)
checks whether the object contains an expected value
(public member function)

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