tardis 0.4.4.0 → 0.5.0

raw patch · 4 files changed

+46/−7 lines, 4 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• ChangeLog.md +3/−0
• README.md +34/−0
• src/Control/Monad/Trans/Tardis.hs +6/−6
• tardis.cabal +3/−1

@@ -0,0 +1,3 @@+* **0.5.0**:+  2024-01-15: Removed MonadTrans instance, replaced with liftTardisT+

@@ -0,0 +1,34 @@+# TardisT++![build status](https://github.com/DanBurton/tardis/actions/workflows/haskell.yml/badge.svg?branch=master)++The State monad allows you+to send information forwards to the future,+or to receive such information from the past.+The Reverse State monad allows you to do the reverse:+send information backwards to the past,+or receive information from the future. ++TardisT is a monad transformer+that provides state operations that allow you+to send information to both the future *and* the past,+as well as receive information from both directions.+It is isomorphic to a StateT on top of a ReverseStateT,+or vice-versa.++See test/Example.hs for an example.++----++This was inspired by Luke Palmer's blog post on+the "reverse state monad".++http://lukepalmer.wordpress.com/2008/08/10/mindfuck-the-reverse-state-monad/++See also:++http://panicsonic.blogspot.com/2007/12/backwards-state-or-power-of-laziness.html++----++(c) 2012 Dan Burton

@@ -1,4 +1,5 @@ {-# LANGUAGE RecursiveDo                     #-}+{-# LANGUAGE TupleSections #-}  -- | The data definition of a "TardisT" -- as well as its primitive operations,@@ -35,6 +36,7 @@      -- * Other   , mapTardisT+  , liftTardisT   , noState   ) where @@ -99,6 +101,10 @@ execTardis :: Tardis bw fw a -> (bw, fw) -> (bw, fw) execTardis t = runIdentity . execTardisT t +-- | An action in the underlying monad (or just functor, really)+-- can also be used in a Tardis by lifting it in.+liftTardisT :: (Functor m) => m a -> TardisT bw fw m a+liftTardisT m = TardisT $ \s -> fmap (,s) m  -- | A function that operates on the internal representation of a Tardis -- can also be used on a Tardis.@@ -131,12 +137,6 @@ instance MonadFix m => Applicative (TardisT bw fw m) where   pure = return   (<*>) = ap---instance MonadTrans (TardisT bw fw) where-  lift m = TardisT $ \s -> do-    x <- m-    return (x, s)  instance MonadFix m => MonadFix (TardisT bw fw m) where   mfix f = TardisT $ \s -> do

@@ -1,5 +1,5 @@ name:                tardis-version:             0.4.4.0+version:             0.5.0 synopsis:            Bidirectional state monad transformer homepage:            https://github.com/DanBurton/tardis bug-reports:         https://github.com/DanBurton/tardis/issues@@ -10,6 +10,8 @@ category:            Control build-type:          Simple cabal-version:       >=1.10+tested-with:         GHC == 9.8.1, GHC == 9.6.3, GHC == 9.4.8+extra-source-files:  README.md, ChangeLog.md  description:   A Tardis is a combination of both a forwards and a backwards