comonad-transformers 0.3 → 0.4

raw patch · 6 files changed

+54/−7 lines, 6 filesdep ~comonadPVP ok

version bump matches the API change (PVP)

Dependency ranges changed: comonad

API changes (from Hackage documentation)

Files

• Control/Comonad/Hoist/Class.hs +4/−3
• Control/Comonad/Trans/Env/Lazy.hs +6/−0
• Control/Comonad/Trans/Env/Strict.hs +6/−0
• Control/Comonad/Trans/Stream.hs +30/−2
• Control/Comonad/Trans/Traced.hs +6/−0
• comonad-transformers.cabal +2/−2

@@ -16,10 +16,11 @@  class ComonadHoist t where   -- | Ideally we would offer a way to lift comonad homomorphisms-  -- but this isn't Haskell 98, so we settle for the most common case.+  -- but this isn't Haskell 98, so we settle for the most common case+  -- here.   ---  -- liftTrans :: (forall a. w a -> v a) -> t w a -> t v a -  -- cohoist = liftTrans (Identity . extract)+  -- > liftTrans :: (forall a. w a -> v a) -> t w a -> t v a +  -- > cohoist = liftTrans (Identity . extract)   cohoist :: Comonad w => t w a -> t Identity a  -- avoiding orphans

@@ -32,6 +32,7 @@ import Control.Comonad.Trans.Class import Control.Comonad.Hoist.Class import Data.Functor.Identity+import Data.Monoid  type Env e = EnvT e Identity data EnvT e w a = EnvT e (w a)@@ -51,6 +52,11 @@ instance Comonad w => Comonad (EnvT e w) where   extract ~(EnvT _ wa) = extract wa   duplicate p@(~(EnvT e wa)) = EnvT e (p <$ wa)++instance (Monoid e, FunctorApply w) => FunctorApply (EnvT e w) where+  ~(EnvT ef wf) <.> ~(EnvT ea wa) = EnvT (ef `mappend` ea) (wf <.> wa)++instance (Monoid e, ComonadApply w) => ComonadApply (EnvT e w)  instance ComonadTrans (EnvT e) where   lower ~(EnvT _ wa) = wa

@@ -32,6 +32,7 @@ import Control.Comonad.Trans.Class import Control.Comonad.Hoist.Class import Data.Functor.Identity+import Data.Monoid  type Env e = EnvT e Identity data EnvT e w a = EnvT e (w a)@@ -57,6 +58,11 @@  instance ComonadHoist (EnvT e) where   cohoist (EnvT e wa) = EnvT e (Identity (extract wa))++instance (Monoid e, FunctorApply w) => FunctorApply (EnvT e w) where+  EnvT ef wf <.> EnvT ea wa = EnvT (ef `mappend` ea) (wf <.> wa)++instance (Monoid e, ComonadApply w) => ComonadApply (EnvT e w)  ask :: EnvT e w a -> e ask (EnvT e _) = e

@@ -1,3 +1,4 @@+-- {-# LANGUAGE FlexibleContexts, UndecidableInstances #-} ----------------------------------------------------------------------------- -- | -- Module      :  Control.Comonad.Trans.Stream@@ -16,12 +17,14 @@ module Control.Comonad.Trans.Stream    (    -- * The Stream comonad-    Stream, stream, runStream+    Stream+  , stream+  , runStream+  , unfolds   -- * The Stream comonad transformer   , StreamT(..)   -- * Operations   , tails-  , unfolds   , unfoldsW   ) where @@ -34,17 +37,26 @@ import Data.Monoid import Data.Traversable +-- | Isomorphic to the definition:+--+-- > data Stream f a = a :< f (Stream f a) type Stream f = StreamT f Identity +-- | cons onto an f-branching stream stream :: a -> f (Stream f a) -> Stream f a  stream a as = StreamT (Identity (a, as)) +-- | uncons from an f-branching stream runStream :: Stream f a -> (a, f (Stream f a)) runStream = runIdentity . runStreamT +-- | unfold a stream from a seed. unfolds :: Functor f => (a -> (b, f a)) -> a -> Stream f b unfolds f a = let (h, t) = f a in stream h (unfolds f <$> t) +-- | The f-branching stream comonad transformer is a comonadic version of+-- the \"ListT done Right\" monad transformer. You can extract the underlying comonadic +-- value by using 'lower' or runStream data StreamT f w a = StreamT { runStreamT :: w (a, f (StreamT f w a)) }  instance (Functor w, Functor f) => Functor (StreamT f w) where@@ -55,6 +67,12 @@   duplicate = StreamT . extend (\w -> (StreamT w, duplicate <$> snd (extract w))) . runStreamT   extend f = StreamT . extend (\w -> (f (StreamT w), extend f <$> snd (extract w))) . runStreamT +instance (ComonadApply w, FunctorApply f) => FunctorApply (StreamT f w) where+  StreamT ffs <.> StreamT aas = StreamT (liftW2 wfa ffs aas) where+    wfa (f,fs) (a,as) = (f a, (<.>) <$> fs <.> as)++instance (ComonadApply w, FunctorApply f) => ComonadApply (StreamT f w)+ instance Functor f => ComonadTrans (StreamT f) where   lower = fmap fst . runStreamT @@ -67,6 +85,16 @@  instance (Traversable w, Traversable f) => Traversable (StreamT f w) where   traverse f (StreamT w) = StreamT <$> traverse (\(a, as) -> (,) <$> f a <*> traverse (traverse f) as) w++{-+instance Show a => Show (Identity a) where+  showsPrec d (Identity a) = showParen (d > 10) $+      showString "Identity " . showsPrec 11 a++instance (Show (w (a, f (StreamT f w a)))) => Show (StreamT f w a) where+  showsPrec d (StreamT w) = showParen (d > 10) $ +      showString "StreamT " . showsPrec 11 w+-}  tails :: Comonad w => StreamT f w a -> f (StreamT f w a) tails = snd . extract . runStreamT

@@ -29,6 +29,7 @@ import Control.Comonad import Control.Comonad.Hoist.Class import Control.Comonad.Trans.Class+import Data.Functor import Data.Functor.Identity import Data.Monoid @@ -54,6 +55,11 @@  instance Monoid m => ComonadHoist (TracedT m) where   cohoist = traced . extract . runTracedT++instance (Monoid m, FunctorApply w) => FunctorApply (TracedT m w) where+  TracedT wf <.> TracedT wa = TracedT ((\mf ma m -> (mf m) (ma m)) <$> wf <.> wa)++instance (Monoid m, ComonadApply w) => ComonadApply (TracedT m w)  trace :: (Comonad w, Monoid m) => m -> TracedT m w a -> a trace m (TracedT wf) = extract wf m

@@ -1,6 +1,6 @@ name:          comonad-transformers category:      Control, Comonads-version:       0.3+version:       0.4 license:       BSD3 cabal-version: >= 1.2 license-file:  LICENSE@@ -18,7 +18,7 @@   build-depends:      base >= 4 && < 4.4,     array >= 0.3.0.1 && < 0.4,-    comonad >= 0.3 && < 0.4,+    comonad >= 0.4 && < 0.5,     transformers >= 0.2.0 && <= 0.3    exposed-modules: