attempt at documenting table crate

src/model/key_table.rs

@@ -113,6 +113,10 @@ impl TableSchema for KeyTable {
 	type E = Key;
 	type Filter = KeyFilter;
 
+	fn updated(&self, _old: Option<Self::E>, _new: Option<Self::E>) {
+		// nothing to do when updated
+	}
+
 	fn matches_filter(entry: &Self::E, filter: &Self::Filter) -> bool {
 		match filter {
 			KeyFilter::Deleted(df) => df.apply(entry.deleted.get()),