[TYPO3-mvc] @uuid, @identity and @transient - is there any use of them?

[Viktor Livakivskyi]

Hi, List.

I was experimenting with ReflectionService and accidentally found out, that buildClassSchema() method checks for following annotations:
@transient - supposed to skip property
@uuid - self-explanatory
@identity - forms array of identities of an object

But I didn't find any use of these properties in a Core. F.e. getUuidPropertyName() and getIdentityProperties() are never used.

Does it appear in TYPO3 CMS, because it is ported from Flow and there is no actual use of these annotations or they can somehow be used?