This component-private struct manages a value_type object in an Optional_Base object. This class provides an abstraction for const value type. An Optional_Base object may contain an object of const type. An assignment to such an Optional_Base object should not succeed. However, unless the Optional_Base object itself is const, it should be possible to change the value of the Optional_Base object using emplace. In order to allow for that, this class manages a non-const object of value_type, but all the accessors return a const adjusted reference to the managed object.
Declared in <bslstl_optional.h>
template<class t_TYPE>
struct Optional_DataImp;| Name | Description |
|---|---|
Optional_DataImp [constructor] | Constructors |
emplace | emplace overloads |
hasValue | Return true if this objects has a value, and false otherwise. |
reset | Destroy the value_type object in d_buffer, if any. |
value | value overloads |
| Name | Description |
|---|---|
Optional_Data<t_TYPE, true> | This partial specialization manages a trivially destructible value_type in Optional_Base. It does not have a user-provided destructor, which makes it is_trivially_destructible itself. |
Optional_Data | This component-private struct manages a value_type object in Optional_Base by inheriting from Optional_DataImp. In addition, this primary template properly destroys the owned instance of t_TYPE in its destructor. |