feat: drop item returns bool, whether item existed

table.go

@@ -171,11 +171,10 @@ func (t *Table[K, V]) Put(key K, value V) (displaced Entry[K, V], err error) {
 	return entry, fmt.Errorf("bad hash: could not place entry after %d resizes", defaultGrowthLimit)
 }
 
-// Drop removes a value for a key in the table. Returns an error if its value
-// cannot be removed.
-func (t *Table[K, V]) Drop(key K) (err error) {
-	t.bucketA.drop(key)
-	t.bucketB.drop(key)
+// Drop removes a value for a key in the table. Returns whether the key had
+// existed.
+func (t *Table[K, V]) Drop(key K) bool {
+	occupied := t.bucketA.drop(key) || t.bucketB.drop(key)
 
 	if t.load() < t.minLoadFactor {
 		// The error is not handled here, because table-shrinking is an internal
@@ -183,7 +182,7 @@ func (t *Table[K, V]) Drop(key K) (err error) {
 		t.shrink()
 	}
 
-	return nil
+	return occupied
 }
 
 // Entries returns an unordered sequence of all key-value pairs in the table.