items property
Items is how many examples the set holds. It is filled only by the single read — a listing does not count, so it is absent there rather than zero.
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? items;