Core.Types.Optional (Visera.Core.Types.Optional)

Core.Types.Optional provides optional type TOptional and tags: NullOpt (no value), InPlace (in-place construct), and FIntrusiveUnsetOptionalState (intrusive optional when the type can represent unset, no extra bool). Like std::optional for return, parameter or member "maybe no value".

Responsibilities

• When HasValue() is true, GetValue() or operator* is safe; otherwise do not dereference.
• Default construct (no value), construct from value, NullOpt, InPlace; copy/move when T supports.
• HasIntrusiveUnsetOptionalState: when true, T can represent unset via comparison with FIntrusiveUnsetOptionalState for zero-overhead optional string etc.

Main types and constants

Type / Constant	Description
TOptional<T>	Optional container; HasValue(), GetValue(), operator*, operator->.
NullOpt	Constant for no value; for construct or assign.
InPlace	In-place construct tag for TOptional(InPlace, args...).
FIntrusiveUnsetOptionalState	Intrusive unset marker type.
HasIntrusiveUnsetOptionalState<T>	Trait: whether T supports intrusive unset.

See also

• Types — Parent module
• Pointer — Smart pointers (optional-like semantics)
• String — Some string types support intrusive optional