BloombergLP::bslstl::Optional_Base

Synopsis

Declared in <bslstl_optional.h>

template<
    class t_TYPE,
    bool t_USES_BSLMA_ALLOC = BloombergLP::bslma::UsesBslmaAllocator<t_TYPE>::value>
class Optional_Base;

Type Aliases

Name	Description
`allocator_type`	This `typedef` is an alias to `bsl::allocator<char>`.
`value_type`	`value_type` is an alias for the underlying `TYPE` upon which this template class is instantiated, and represents the type of the managed object. The name is chosen so it is compatible with the `std::optional` implementation.

Member Functions

Name	Description
`operator=`	Assignment operators
`emplace`	`emplace` overloads
`get_allocator`	Return allocator used for construction of `value_type`.
`has_value`	Return `false` if this object is disengaged, and `true` otherwise.
`operator*`	Dereference operators
`operator->`	Member access operators
`reset`	Reset this object to the default constructed state (i.e., to a disengaged state).
`swap`	Efficiently exchange the value of this object with the value of the specified `other` object. This method provides the no-throw exception-safety guarantee if the template parameter `t_TYPE` provides that guarantee and the result of the `hasValue` method for the two objects being swapped is the same. The behavior is undefined unless this object was created with the same allocator as `other`.
`value`	`value` overloads
`value_or`	`value_or` overloads
`operator BloombergLP::bslmf::NestedTraitDeclaration<Optional_Base, IsBitwiseCopyable, BloombergLP::bslmf::IsBitwiseCopyable<t_TYPE>::value>`	Nested trait declaration for `bslmf::IsBitwiseCopyable`.
`operator BloombergLP::bslmf::NestedTraitDeclaration<Optional_Base, IsBitwiseMoveable, BloombergLP::bslmf::IsBitwiseMoveable<t_TYPE>::value>`	Nested trait declaration for `bslmf::IsBitwiseMoveable`.
`operator BloombergLP::bslmf::NestedTraitDeclaration<Optional_Base, UsesAllocatorArgT>`	Nested trait declaration for `bslmf::UsesAllocatorArgT`.
`operator BloombergLP::bslmf::NestedTraitDeclaration<Optional_Base, UsesBslmaAllocator>`	Nested trait declaration for `bslma::UsesBslmaAllocator`.
`operator bool`	Return `false` if this object is disengaged, and `true` otherwise.

Protected Type Aliases

Name	Description
`AllocType`	This `typedef` is an alias to `allocator_type`.

Protected Member Functions

Name	Description
`Optional_Base` [constructor]	Constructors
`assignOrEmplace`	If `this` holds an object, assign to that object the value of the specified `rhs`, converted to `t_TYPE`. Otherwise, construct a held object from `rhs`, converted to `t_TYPE`. The allocators of `this` and `rhs` remain unchanged.
`dereferenceRaw`	`dereferenceRaw` overloads

Specializations

Name	Description
`Optional_Base<t_TYPE, false>`	Specialization of `Optional_Base` for `value_type` that is not allocator-aware when `std::optional` is available.

Derived Classes

Name	Description
`optional`