Implement application::Update for ()

runtime/src/task.rs

@@ -283,10 +283,7 @@ impl<T, E> Task<Result<T, E>> {
     }
 }
 
-impl<T> From<()> for Task<T>
+impl<T> From<()> for Task<T> {
-where
-    T: MaybeSend + 'static,
-{
     fn from(_value: ()) -> Self {
         Self::none()
     }

src/application.rs

@@ -417,6 +417,16 @@ pub trait Update<State, Message> {
     ) -> impl Into<Task<Message>>;
 }
 
+impl<State, Message> Update<State, Message> for () {
+    fn update(
+        &self,
+        _state: &mut State,
+        _message: Message,
+    ) -> impl Into<Task<Message>> {
+        ()
+    }
+}
+
 impl<T, State, Message, C> Update<State, Message> for T
 where
     T: Fn(&mut State, Message) -> C,

src/lib.rs

@@ -345,8 +345,6 @@ pub type Result = std::result::Result<(), Error>;
 ///
 /// This is equivalent to chaining [`application()`] with [`Application::run`].
 ///
-/// [`program`]: program()
-///
 /// # Example
 /// ```no_run
 /// use iced::widget::{button, column, text, Column};