std::expected<T,E>::error_or
From cppreference.com
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 returns default_value.
1) If std::is_copy_constructible_v<E> or std::is_convertible_v<G, E> is false, the program is ill-formed.
2) If std::is_move_constructible_v<E> or std::is_convertible_v<G, E> is false, the program is ill-formed.
Parameters
default_value | - | the value to use in case *this does not contain an unexpected value |
Type requirements |
Return value
1) has_value() ? std::forward<G>(default_value) : error()
2) has_value() ? std::forward<G>(default_value) : std::move(error())
Example
This section is incomplete Reason: no example |
See also
returns the unexpected value (public member function) |