disposed property
Disposed is how many published values retention has taken. It is DERIVED from the lowest surviving sequence, so it cannot drift from what it describes, and it is reported because a retention that binds is a fact an operator must be able to read rather than a silence.
Please note: This property should have been non-nullable! Since the specification file does not include a default value (using the "default:" property), however, the generated source code must fall back to having a nullable type. Consider adding a "default:" property in the specification file to hide this note.
Implementation
int? disposed;