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

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constexpr explicit operator bool ( ) const noexcept ;	(1)	(since C++23)
constexpr bool has_value ( ) const noexcept ;	(2)	(since C++23)

Checks whether * this represents an expected value.

Return value

has_val

Notes

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

Example

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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

operator-> operator*	accesses the expected value (public member function)
error	returns the unexpected value (public member function)

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

Return value

Notes

Example

See also

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