keera-hails-reactive-yampa (empty) → 0.0.3.3

raw patch · 4 files changed

+197/−0 lines, 4 filesdep +Yampadep +basedep +keera-callbackssetup-changed

Dependencies added: Yampa, base, keera-callbacks, keera-hails-reactivevalues, time

Files

• LICENSE +30/−0
• Setup.hs +2/−0
• keera-hails-reactive-yampa.cabal +62/−0
• src/Hails/Yampa.hs +103/−0

@@ -0,0 +1,30 @@+Copyright (c) 2015, Ivan Perez++All rights reserved.++Redistribution and use in source and binary forms, with or without+modification, are permitted provided that the following conditions are met:++    * Redistributions of source code must retain the above copyright+      notice, this list of conditions and the following disclaimer.++    * Redistributions in binary form must reproduce the above+      copyright notice, this list of conditions and the following+      disclaimer in the documentation and/or other materials provided+      with the distribution.++    * Neither the name of Ivan Perez nor the names of other+      contributors may be used to endorse or promote products derived+      from this software without specific prior written permission.++THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain

@@ -0,0 +1,62 @@+-- hails.cabal auto-generated by cabal init. For additional options,+-- see+-- http://www.haskell.org/cabal/release/cabal-latest/doc/users-guide/authors.html#pkg-descr.+-- The name of the package.+Name:                keera-hails-reactive-yampa++-- The package version. See the Haskell package versioning policy+-- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for+-- standards guiding when and how versions should be incremented.+Version:             0.0.3.3++-- A short (one-line) description of the package.+Synopsis:            Haskell on Rails - FRP Yampa Signal Functions as RVs++-- A longer description of the package.+Description:         Yampa-driven Functional Reactive Signal Functions,+                     as reactive values.++-- URL for the project homepage or repository.+Homepage:            http://www.keera.es/blog/community/++-- The license under which the package is released.+License:             BSD3++-- The file containing the license text.+License-file:        LICENSE++-- The package author(s).+Author:              Ivan Perez++-- An email address to which users can send suggestions, bug reports,+-- and patches.+Maintainer:          ivan.perez@keera.co.uk++-- A copyright notice.+-- Copyright:           ++Category:            Development++Build-type:          Simple++-- Extra files to be distributed with the package, such as examples or+-- a README.+-- Extra-source-files:  ++-- Constraint on the version of Cabal needed to build this package.+Cabal-version:       >=1.2++Library+  hs-source-dirs: src/+  +  ghc-options: -Wall -fno-warn-unused-do-bind -O2++  -- Modules exported by the library.+  Exposed-modules: Hails.Yampa+  +  -- Packages needed in order to build this package.+  Build-depends: base >= 4 && < 5+               , keera-hails-reactivevalues+               , keera-callbacks+               , time+               , Yampa

@@ -0,0 +1,103 @@+-- {-# LANGUAGE UndecidableInstances #-}+-- {-# LANGUAGE FlexibleInstances    #-}+module Hails.Yampa where++import Control.Monad (when, void)+import Data.CBMVar+import Data.IORef+import Data.Maybe (fromJust)+import Data.ReactiveValue+import Data.Time.Clock+import FRP.Yampa++-- | Define a couple of RVs connected by an SF, so that+-- writing to one makes the SF process the value and make+-- the result available in a readable RV.+yampaReactiveDual :: a -> SF a b+                  -> IO (ReactiveFieldWrite IO a, ReactiveFieldRead IO b)+yampaReactiveDual initial sf = do +  mvar <- newCBMVar Nothing++  -- Initial clock+  initialClock <- getCurrentTime+  lastTimeR    <- newIORef initialClock++  -- Reactimation Handle+  rh <- reactInit+          -- Initial value+          (return initial)+          -- Actuation+          (\_ changed output -> do when changed $ writeCBMVar mvar (Just output)+                                   return False+          )+          -- Processing+          sf++  -- RV fields+  let getter   = fmap fromJust $ readCBMVar mvar+      setter y = void $ do -- Calculate time delta+                           newTime  <- getCurrentTime+                           lastTime <- readIORef lastTimeR+                           let dt = realToFrac $ diffUTCTime newTime lastTime+                           writeIORef lastTimeR newTime++                           -- Run FRP system+                           react rh (dt, Just y)++      notifier evH = installCallbackCBMVar mvar evH++  let rvRead  = ReactiveFieldRead getter notifier+      rvWrite = ReactiveFieldWrite setter+                          +  return (rvWrite, rvRead)++-- | Create an RV that processes the value+-- with an SF every time it is written.+yampaReactive :: a -> SF a a -> IO (ReactiveFieldReadWrite IO a)+yampaReactive initial sf = do +  mvar <- newCBMVar initial++  -- Initial clock+  initialClock <- getCurrentTime+  lastTimeR    <- newIORef initialClock++  -- Reactimation Handle+  rh <- reactInit+          -- Initial value+          (readCBMVar mvar)+          -- Actuation+          (\_ changed output -> do when changed $ writeCBMVar mvar output+                                   return False+          )+          -- Processing+          sf++  -- RV fields+  let getter   = readCBMVar mvar+      setter y = void $ do -- Calculate time delta+                           newTime  <- getCurrentTime+                           lastTime <- readIORef lastTimeR+                           let dt = realToFrac $ diffUTCTime newTime lastTime+                           writeIORef lastTimeR newTime++                           -- Run FRP system+                           react rh (dt, Just y)++      notifier = installCallbackCBMVar mvar+                          +  return $ ReactiveFieldReadWrite setter getter notifier++-- | Alternative (simpler) definition to 'yampaReactive'+yampaReactive' :: a -> SF a a -> IO (ReactiveFieldReadWrite IO a)+yampaReactive' initial sf = do+  (rvW, rvR) <- yampaReactiveDual initial sf+  return $ combineRVReadWrite rvR rvW++-- | To be moved to Data.ReactiveValue+combineRVReadWrite :: (ReactiveValueRead r1 a m,  ReactiveValueWrite r2 a m)+                   => r1 -> r2 -> ReactiveFieldReadWrite m a+combineRVReadWrite rvR rvW = ReactiveFieldReadWrite setter getter notifier+  where getter   = reactiveValueRead rvR+        setter   = reactiveValueWrite rvW+        notifier = reactiveValueOnCanRead rvR+