std::expected<T,E>::error
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std::expected
expected::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.
If has_value() is true, the behavior is undefined.
(until C++26)If has_value() is true:
- If the implementation is hardened, a contract violation occurs. Moreover, if the contract-violation handler returns under "observe" evaluation semantic, the behavior is undefined.
- If the implementation is not hardened, the behavior is undefined.
[edit] Return value
1,2)
unex 3,4) std::move(
unex )[edit] Example
This section is incomplete
Reason: no example
Reason: no example