blanket impl of Update.undo()

lootalot_db/src/lib.rs

@@ -42,7 +42,7 @@ pub fn create_pool() -> Pool {
 
 
 /// Every possible update which can happen during a query
-#[derive(Serialize, Debug)]
+#[derive(Serialize, Deserialize, Debug)]
 pub enum Update {
     Wealth(Wealth),
     ItemAdded(Item),
@@ -51,6 +51,20 @@ pub enum Update {
     ClaimRemoved(Claim),
 }
 
+impl Update {
+    /// Change back what has been updated
+    fn undo(self) -> QueryResult<()> {
+        match self {
+            Update::Wealth(diff) => {},
+            Update::ItemAdded(item) => {},
+            Update::ItemRemoved(item) => {},
+            Update::ClaimAdded(claim) => {},
+            Update::ClaimRemoved(claim) => {},
+        };
+        Ok(())
+    }
+}
+
 /// Every value which can be queried
 #[derive(Debug)]
 pub enum Value {