ludus::foundation::identity::Handle¶

Struct

Nonowning reference to one runtime incarnation in one owning registry.

Tag is a compile-time domain marker: handles of different tags are distinct types with no conversion, so an entity handle cannot be passed where a texture handle is expected. The owner field distinguishes two registries of the same domain at run time. Neither check replaces the other.

All-zero is the canonical null value. Owner zero or generation zero is never issued; slot zero is a valid first slot. Equality compares the complete value, including the owner. Neither equality nor IsNull() says anything about liveness: only the issuing registry can validate a handle. A handle does not own its object, pin its memory, or contain a pointer, UUID or manager lookup.

The value is trivially copyable, 16 bytes, and safe to copy across threads; the registry that resolves it defines its own synchronization. Do not persist it: owner tokens are process-scoped (see TryIssueLifetimeId()).

Template parameter	Description
`Tag`	Domain marker type; it is never instantiated.

Declared in modules/foundation/identity/include/ludus/foundation/identity/handle.hpp

#include <ludus/foundation/identity/handle.hpp>

template <typename Tag>
struct ludus::foundation::identity::Handle final

Fields¶

Owner¶

uint64 ludus::foundation::identity::Handle< Tag >::Owner = 0

Lifetime token of the issuing registry; zero only in the null handle.

Related types: uint64

Declared in modules/foundation/identity/include/ludus/foundation/identity/handle.hpp

Slot¶

uint32 ludus::foundation::identity::Handle< Tag >::Slot = 0

Registry slot index; zero is a valid slot.

Related types: uint32

Declared in modules/foundation/identity/include/ludus/foundation/identity/handle.hpp

Generation¶

uint32 ludus::foundation::identity::Handle< Tag >::Generation = 0

Incarnation of the slot; zero only in the null handle.

Related types: uint32

Declared in modules/foundation/identity/include/ludus/foundation/identity/handle.hpp

Methods¶

operator==¶

constexpr bool ludus::foundation::identity::Handle< Tag >::operator==(const Handle &) const noexcept=default

Compare all fields exactly. Equal handles name the same incarnation, not a live one.

Related types: Handle

Declared in modules/foundation/identity/include/ludus/foundation/identity/handle.hpp

IsNull¶

LUDUS_INLINE constexpr bool ludus::foundation::identity::Handle< Tag >::IsNull() const noexcept

Report whether this is the canonical all-zero null value. A nonnull handle may still be malformed, stale or owned by another registry.

Declared in modules/foundation/identity/include/ludus/foundation/identity/handle.hpp