monoid-transformer 0.0.2 → 0.0.3

raw patch · 6 files changed

+80/−2 lines, 6 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• monoid-transformer.cabal +6/−2
• src/Data/Monoid/Applicative.hs +20/−0
• src/Data/Monoid/Monad.hs +22/−0
• src/Data/Monoid/MonadicEndo.hs +18/−0
• src/Data/Monoid/Reader.hs +7/−0
• src/Data/Monoid/State.hs +7/−0

@@ -1,5 +1,5 @@ Name:             monoid-transformer-Version:          0.0.2+Version:          0.0.3 License:          BSD3 License-File:     LICENSE Author:           Henning Thielemann <haskell@henning-thielemann.de>@@ -14,6 +14,7 @@   There is no Writer transformer.   It's vice versa: The Writer monad transforms a monoid to a monad. Tested-With:       GHC==6.8.2+Tested-With:       GHC==7.8.2 Cabal-Version:     >=1.6 Build-Type:        Simple @@ -24,7 +25,7 @@ Source-Repository this   type:     darcs   location: http://code.haskell.org/~thielema/monoid/-  tag:      0.0.2+  tag:      0.0.3   Library@@ -33,6 +34,9 @@   GHC-Options:      -Wall   Hs-Source-Dirs:   src   Exposed-Modules:+    Data.Monoid.Applicative+    Data.Monoid.Monad     Data.Monoid.Reader     Data.Monoid.State+    Data.Monoid.MonadicEndo     Data.Monoid.Transformer

@@ -0,0 +1,20 @@+module Data.Monoid.Applicative where++import qualified Data.Monoid.Transformer as MonoidTrans++import Control.Applicative (Applicative, pure, liftA2, )+import Data.Monoid (Monoid, mempty, mappend, )++{- |+Sequence applicative functors and combine their functorial results with 'mappend'.+-}+newtype T f a = Cons {run :: f a}+++instance (Applicative f, Monoid a) => Monoid (T f a) where+   mempty = Cons $ pure mempty+   mappend (Cons x) (Cons y) =+      Cons $ liftA2 mappend x y++instance (Applicative f) => MonoidTrans.C (T f) where+   lift = Cons . pure

@@ -0,0 +1,22 @@+module Data.Monoid.Monad where++import qualified Data.Monoid.Transformer as MonoidTrans++import Control.Monad (liftM2, )+import Data.Monoid (Monoid, mempty, mappend, )++{- |+Sequence actions and combine their monadic results with 'mappend'.++This type could be omitted, if 'Monad' would be a sub-class of 'Applicative'.+-}+newtype T m a = Cons {run :: m a}+++instance (Monad m, Monoid a) => Monoid (T m a) where+   mempty = Cons $ return mempty+   mappend (Cons x) (Cons y) =+      Cons $ liftM2 mappend x y++instance (Monad m) => MonoidTrans.C (T m) where+   lift = Cons . return

@@ -0,0 +1,18 @@+module Data.Monoid.MonadicEndo where++import Data.Monoid (Monoid, mempty, mappend, )++{- |+Like Data.Monoid.Endo but with monadic result.+'mempty' is 'return' and 'mappend' is '<=<'.++Useful e.g. for handling options with GetOpt.+-}+newtype T m a = Cons {run :: a -> m a}+++instance Monad m => Monoid (T m a) where+   mempty = Cons return+   mappend (Cons x) (Cons y) =+      Cons $ (x =<<) . y+--      Cons $ x <=< y

@@ -2,8 +2,15 @@  import qualified Data.Monoid.Transformer as MonoidTrans import Data.Monoid (Monoid, mempty, mappend, )+import Data.Functor (Functor, fmap, )+import Data.Function (const, ($), (.), ) +import Prelude () ++{- |+Could also be written as @Monoid.Applicative (Monad.Trans.Reader r) a@.+-} newtype T r a = Cons {run :: r -> a}  pure :: a -> T r a

@@ -2,7 +2,12 @@  import qualified Data.Monoid.Transformer as MonoidTrans import Data.Monoid (Monoid, mempty, mappend, )+import Data.Functor (Functor, fmap, )+import Data.Function (const, ($), (.), )+import Data.Tuple (fst, snd, ) +import Prelude ()+ {- | This resembles the pure State monad. However, State in transformers is a StateT@@ -11,6 +16,8 @@ I hope I have the more natural parameter order for 'evaluate' in contrast to @mtl@ and @transformers@. However, it is different from the parameter order of 'run'.++Could also be written as @Monoid.Applicative (Monad.Trans.State s) a@. -} newtype T s a = Cons {run :: s -> (a,s)}