std:: bad_optional_access
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Defined in header
<optional>
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||
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class
bad_optional_access
;
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(since C++17) | |
Defines a type of object to be thrown by std::optional::value when accessing an optional object that does not contain a value.
Inheritance diagram
Member functions
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(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::bad_optional_access:: bad_optional_access
|
bad_optional_access
(
)
noexcept
;
|
(1) | (since C++17) |
|
bad_optional_access
(
const
bad_optional_access
&
other
)
noexcept
;
|
(2) | (since C++17) |
Constructs a new
bad_optional_access
object with an implementation-defined null-terminated byte string which is accessible through
what()
.
std::bad_optional_access
then
std::
strcmp
(
what
(
)
, other.
what
(
)
)
==
0
.
Parameters
| other | - | another exception object to copy |
std::bad_optional_access:: operator=
|
bad_optional_access
&
operator
=
(
const
bad_optional_access
&
other
)
noexcept
;
|
(since C++17) | |
Assigns the contents with those of
other
. If
*
this
and
other
both have dynamic type
std::bad_optional_access
then
std::
strcmp
(
what
(
)
, other.
what
(
)
)
==
0
after assignment.
Parameters
| other | - | another exception object to assign with |
Return value
* this
std::bad_optional_access:: what
|
virtual
const
char
*
what
(
)
const
noexcept
;
|
(since C++17) | |
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:: 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
)
|