From 6d585f5508f5efbec8f5fbcfc9b01eafb9606227 Mon Sep 17 00:00:00 2001 From: Jens Nolte <git@queezle.net> Date: Sun, 11 Oct 2020 00:09:24 +0200 Subject: [PATCH] Implement Disposable instance for Maybe (Disposable a) --- src/lib/Qd/Observable.hs | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/lib/Qd/Observable.hs b/src/lib/Qd/Observable.hs index fcf3869..95913ca 100644 --- a/src/lib/Qd/Observable.hs +++ b/src/lib/Qd/Observable.hs @@ -46,7 +46,9 @@ instance Disposable SubscriptionHandle where dispose = unsubscribe instance Disposable RegistrationHandle where dispose = deregister - +instance Disposable a => Disposable (Maybe a) where + dispose = mapM_ dispose + class Observable v o | o -> v where getValue :: o -> IO (ObservableState v) subscribe :: o -> (ObservableMessage v -> IO ()) -> IO SubscriptionHandle -- GitLab