std::experimental:: bad_optional_access

From cppreference.com
Defined in header <experimental/optional>
class bad_optional_access ;
(library fundamentals TS)

Defines a type of object to be thrown by std::experimental::optional::value when accessing an optional object that does not contain a value.

cpp/error/exception cpp/error/logic error std-bad optional access-inheritance.svg

Inheritance diagram

Member functions

(constructor)
constructs a new bad_optional_access object
(public member function)
operator=
replaces the bad_optional_access object
(public member function)
what
returns the explanatory string
(public member function)

std::experimental::bad_optional_access:: bad_optional_access

bad_optional_access ( ) noexcept ;
(1) (library fundamentals TS)
bad_optional_access ( const bad_optional_access & other ) noexcept ;
(2) (library fundamentals TS)

Constructs a new bad_optional_access object with an implementation-defined null-terminated byte string which is accessible through what() .

1) Default constructor.
2) Copy constructor. If * this and other both have dynamic type std::experimental::bad_optional_access then std:: strcmp ( what ( ) , other. what ( ) ) == 0 .

Parameters

other - another exception object to copy

std::experimental::bad_optional_access:: operator=

bad_optional_access & operator = ( const bad_optional_access & other ) noexcept ;
(library fundamentals TS)

Assigns the contents with those of other . If * this and other both have dynamic type std::experimental::bad_optional_access then std:: strcmp ( what ( ) , other. what ( ) ) == 0 after assignment.

Parameters

other - another exception object to assign with

Return value

* this

std::experimental::bad_optional_access:: what

virtual const char * what ( ) const noexcept ;
(library fundamentals TS)

Returns the explanatory string.

Parameters

(none)

Return value

Pointer to a null-terminated string with explanatory information. The string is suitable for conversion and display as a std::wstring . The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function (e.g. copy assignment operator) on the exception object is called.

The returned string is encoded with the ordinary literal encoding during constant evaluation.

(since C++26)

Notes

Implementations are allowed but not required to override what() .

Inherited from std:: logic_error

Inherited from std:: exception

Member functions

[virtual]
destroys the exception object
(virtual public member function of std::exception )
[virtual]
returns an explanatory string
(virtual public member function of std::exception )