Create a nullable object that has the null value; use the specified allocator (e.g., the address of a bslma::Allocator object) to supply memory for subsequent values assigned to this object. Note that this constructor will not participate in overload resolution unless TYPE is allocator aware.
Declared in <bdlb_nullablevalue.h>
NullableValue(
bsl::nullopt_t const&,
allocator_type const& allocator) noexcept;