update to 4.0.1

+## [4.0.1] 
+- Fix changelog
+
 ## [4.0.0] 
 - Added append function to StateMixin. Now is possible track loading, success and error handle of your application with ONE LINE OF CODE. Ex: append(()=> api.getUser);
 - Migrate to null-safety 
 - Added ScrollMixin to controllers
 - Added loadingMore status to RxStatus
-- Breaking: It is not possible to initialize Rx with null values.
+- Fix content-type qual null (@katekko)
+- Made GetInstance non nullable (@eduardoflorence)
+- Fix multi-parameters url (@iMrLopez)
+- Fix Expected value of SkDeletable error (@obadajasm)
+- Added triggers, an Rx method that triggers events, even if they are the same as the previous event (@RafaRuiz)
+- Improve docs: (@CNAD666), (@dhhAndroid), (@Jackylee1992),
+
+Switching to null-safety:
+You can continue using GetX as normal, with as little breaking changes as possible.
+It is still possible to declare the var.obs variable, and this remains the preferred way, forcing null-safety and giving you all the security that sound null-safety delivers to your app. However, if you need to use null, we also provide a solution for you.
+Declare the variables with `?` Ex: `final Rx<int?> count = 0.obs`.
+You can also use custom Rxn types with null-safety:
+`RxInt` == not nullable
+`RxnInt` == nullable.
 
 ## [3.25.6] 
 - Added documentation in French (@kamazoun)

@@ -20,6 +20,7 @@ linter:
     # INCLUDE_FIX (copy of effective dart 1.2.0)
     # STYLE
     camel_case_types: true
+    close_sinks: true
     camel_case_extensions: true
     library_names: true
     file_names: true

@@ -90,7 +90,7 @@ class BaseWebSocket {
   }
 
   void close([int? status, String? reason]) {
-    if (socket != null) socket!.close(status, reason);
+    socket?.close(status, reason);
   }
 
   void send(dynamic data) {

@@ -82,9 +82,7 @@ class BaseWebSocket {
   }
 
   void close([int? status, String? reason]) {
-    if (socket != null) {
-      socket!.close(status, reason);
-    }
+    socket?.close(status, reason);
   }
 
   void send(dynamic data) async {

@@ -95,9 +95,11 @@ mixin RxObjectMixin<T> on NotifyManager<T> {
   /// Updates the [value] and adds it to the stream, updating the observer
   /// Widget, only if it's different from the previous value.
   set value(T val) {
+    if (subject.isClosed) return;
     if (_value == val && !firstRebuild) return;
     firstRebuild = false;
     _value = val;
+
     subject.add(_value);
   }
 
@@ -236,15 +238,32 @@ abstract class _RxImpl<T> extends RxNotifier<T> with RxObjectMixin<T> {
   }
 }
 
-extension RxBoolExt on Rx<bool> {}
-
-/// Rx class for `bool` Type.
-class RxBool extends _RxImpl<bool> {
+class RxBool extends Rx<bool> {
   RxBool(bool initial) : super(initial);
+  @override
+  String toString() {
+    return value ? "true" : "false";
+  }
+}
 
-  bool? get isTrue => value;
+class RxnBool extends Rx<bool?> {
+  RxnBool(bool initial) : super(initial);
+  @override
+  String toString() {
+    if (value == null) {
+      return "null";
+    } else if (value) {
+      return "true";
+    } else {
+      return "false";
+    }
+  }
+}
+
+extension RxBoolExt on Rx<bool> {
+  bool get isTrue => value;
 
-  bool get isFalse => !isTrue!;
+  bool get isFalse => !isTrue;
 
   bool operator &(bool other) => other && value;
 
@@ -257,14 +276,43 @@ class RxBool extends _RxImpl<bool> {
   /// FIXME: why return this? fluent interface is not
   ///  not really a dart thing since we have '..' operator
   // ignore: avoid_returning_this
-  RxBool toggle() {
+  Rx<bool> toggle() {
     subject.add(_value = !_value);
     return this;
   }
+}
 
-  @override
-  String toString() {
-    return value ? "true" : "false";
+extension RxnBoolExt on Rx<bool?> {
+  bool? get isTrue => value;
+
+  bool? get isFalse {
+    if (value != null) return !isTrue!;
+  }
+
+  bool? operator &(bool other) {
+    if (value != null) {
+      return other && value!;
+    }
+  }
+
+  bool? operator |(bool other) {
+    if (value != null) {
+      return other || value!;
+    }
+  }
+
+  bool? operator ^(bool other) => !other == value;
+
+  /// Toggles the bool [value] between false and true.
+  /// A shortcut for `flag.value = !flag.value;`
+  /// FIXME: why return this? fluent interface is not
+  ///  not really a dart thing since we have '..' operator
+  // ignore: avoid_returning_this
+  Rx<bool?>? toggle() {
+    if (_value != null) {
+      subject.add(_value = !_value!);
+      return this;
+    }
   }
 }
 

 name: get
 description: Open screens/snackbars/dialogs without context, manage states and inject dependencies easily with GetX.
-version: 4.0.0
+version: 4.0.1
 homepage: https://github.com/jonataslaw/getx
 
 environment:

@@ -94,6 +94,7 @@ void main() {
 
     await Future.delayed(Duration.zero);
     expect(count, 555);
+    controller.close();
   });
 
   test('Rx same value will not call the same listener when `call`', () async {