restore list's state after empty

library.json

@@ -1,27 +1,24 @@
 {
-    "name": "ha-mqtt",
-    "version": "1.0.0",
-    "description": "Home Assistant classes for integration with MQTT auto discovery",
-    "repository":
+  "$schema": "https://raw.githubusercontent.com/platformio/platformio-core/develop/platformio/assets/schema/library.json",
+  "name": "ha-mqtt",
+  "version": "1.0.1",
+  "description": "Home Assistant classes for integration with MQTT auto discovery",
+  "repository": {
+    "type": "git",
+    "url": "https://git.hodos.ro/arduino/ha-mqtt.git"
+  },
+  "authors": [
     {
-      "type": "git",
-      "url": "https://git.hodos.ro/arduino/ha-mqtt.git"
-    },
-    "authors":
-    [
-      {
-        "name": "Nicu Hodos",
-        "email": "nicu@hodos.ro",
-        "maintainer": true
-      }
-    ],
-    "dependencies":
-    {
-      "bblanchon/ArduinoJson": "6.21.5",
-      "arkhipenko/TaskScheduler": "^3.7.0",
-      "marvinroger/AsyncMqttClient": "^0.9.0"
-    },
-    "license": "MIT",
-    "frameworks": "arduino",
-    "platforms": "*"
-  }
+      "name": "Nicu Hodos",
+      "email": "nicu@hodos.ro",
+      "maintainer": true
+    }
+  ],
+  "dependencies": {
+    "bblanchon/ArduinoJson": "6.21.5",
+    "marvinroger/AsyncMqttClient": "^0.9.0"
+  },
+  "license": "MIT",
+  "frameworks": "arduino",
+  "platforms": "*"
+}

src/utils.h

@@ -30,6 +30,7 @@ struct List {
             delete c;
             c = n;
         }
+        first = last = nullptr;
     }
 
 };