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std::expected<T,E>::operator bool, std::expected<T,E>::has_value

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< cpp‎ | utility‎ | expected
 
 
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constexpr explicit operator bool() const noexcept;
(since C++23)
constexpr bool has_value() const noexcept;
(since C++23)

Checks whether *this contains an expected value.

Contents

[edit] Parameters

(none)

[edit] Return value

true if *this contains an expected value, false if *this contains an unexpected value.

[edit] Notes

A std::expected object is never empty. If has_value() returns true, operator* can be used to access the contained value; otherwise, error() can be used.

[edit] Example

[edit] See also

accesses the expected value
(public member function) [edit]
returns the unexpected value
(public member function) [edit]