SentinelKind class Null safety
SentinelKind is used to distinguish different kinds of
Adding new values to
SentinelKind is considered a backwards compatible
change. Clients must handle this gracefully.
- kBeingInitialized → const String
Indicates that a variable or field is in the process of being initialized.
- kCollected → const String
Indicates that the object referred to has been collected by the GC.
- kExpired → const String
Indicates that an object id has expired.
- kFree → const String
Reserved for future use.
- kNotInitialized → const String
Indicates that a variable or field has not been initialized.
- kOptimizedOut → const String
Indicates that a variable has been eliminated by the optimizing compiler.