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

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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.

default_value	-	the value to use in case * this does not contain an unexpected value
Type requirements

1) has_value ( ) ? std:: forward < G > ( default_value ) : error ( )

2) has_value ( ) ? std:: forward < G > ( default_value ) : std :: move ( error ( ) )

This section is incomplete
Reason: no example

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Member functions
expected::expected
expected::~expected
expected::operator=
Observers
expected::operator-> expected::operator*
expected::operator bool expected::has_value
expected::value
expected::error
expected::value_or
expected::error_or
Monadic operations
expected::and_then
expected::or_else
expected::transform
expected::transform_error
Modifiers
expected::emplace
expected::swap
Non-member functions
operator== (std::expected)
swap (std::expected)
Helper classes
unexpected
bad_expected_access
unexpect_t unexpect