From 0931ef14ec1fe895ac5003aa174fe5e9b3a3c72c Mon Sep 17 00:00:00 2001
From: Jens Nolte <git@queezle.net>
Date: Tue, 1 Sep 2020 00:35:13 +0200
Subject: [PATCH] Rename Observable to SomeObservable
---
src/lib/Qd/Observable.hs | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/src/lib/Qd/Observable.hs b/src/lib/Qd/Observable.hs
index 983916e..95e6b89 100644
--- a/src/lib/Qd/Observable.hs
+++ b/src/lib/Qd/Observable.hs
@@ -1,5 +1,5 @@
module Qd.Observable (
- Observable(..),
+ SomeObservable(..),
IsObservable(..),
subscribe',
SubscriptionHandle(..),
@@ -39,29 +39,29 @@ newtype SubscriptionHandle = SubscriptionHandle { unsubscribe :: IO () }
class IsObservable v o | o -> v where
getValue :: o -> IO (ObservableState v)
subscribe :: o -> (ObservableMessage v -> IO ()) -> IO SubscriptionHandle
- mapObservable :: (v -> IO a) -> o -> Observable a
- mapObservable f = Observable . MappedObservable f
+ mapObservable :: (v -> IO a) -> o -> SomeObservable a
+ mapObservable f = SomeObservable . MappedObservable f
subscribe' :: IsObservable v o => o -> (SubscriptionHandle -> ObservableMessage v -> IO ()) -> IO SubscriptionHandle
subscribe' observable callback = mfix $ \subscription -> subscribe observable (callback subscription)
type Callback v = ObservableMessage v -> IO ()
--- | Wraps IsObservable in a concrete type
-data Observable v = forall o. IsObservable v o => Observable o
-instance IsObservable v (Observable v) where
- getValue (Observable o) = getValue o
- subscribe (Observable o) = subscribe o
- mapObservable f (Observable o) = mapObservable f o
+-- | Existential quantification wrapper for the Observable type class.
+data SomeObservable v = forall o. IsObservable v o => SomeObservable o
+instance IsObservable v (SomeObservable v) where
+ getValue (SomeObservable o) = getValue o
+ subscribe (SomeObservable o) = subscribe o
+ mapObservable f (SomeObservable o) = mapObservable f o
-instance Functor Observable where
+instance Functor SomeObservable where
fmap f = mapObservable (return . f)
data MappedObservable b = forall a o. IsObservable a o => MappedObservable (a -> IO b) o
instance IsObservable v (MappedObservable v) where
getValue (MappedObservable f observable) = mapObservableState f =<< getValue observable
subscribe (MappedObservable f observable) callback = subscribe observable (callback <=< mapObservableMessage f)
- mapObservable f1 (MappedObservable f2 upstream) = Observable $ MappedObservable (f1 <=< f2) upstream
+ mapObservable f1 (MappedObservable f2 upstream) = SomeObservable $ MappedObservable (f1 <=< f2) upstream
newtype BasicObservable v = BasicObservable (MVar (ObservableState v, HM.HashMap Unique (Callback v)))
--
GitLab