The ID a rule carries now: id itself, or, for a retired ID, the ID it was renamed to (following a chain of renames). An unknown ID is returned as it is, so a caller can map every ID it holds without checking first.
id
The ID a rule carries now:
iditself, or, for a retired ID, the ID it was renamed to (following a chain of renames). An unknown ID is returned as it is, so a caller can map every ID it holds without checking first.