src/Reflex/BehaviorWriter/Class.hs · reflex

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1{-|

2Module: Reflex.BehaviorWriter.Class

3Description: This module defines the 'BehaviorWriter' class

4-}

5{-# LANGUAGE CPP #-}

6{-# LANGUAGE ConstraintKinds #-}

7{-# LANGUAGE FlexibleInstances #-}

8{-# LANGUAGE FunctionalDependencies #-}

9{-# LANGUAGE UndecidableInstances #-}

10#ifdef USE_REFLEX_OPTIMIZER

11{-# OPTIONS_GHC -fplugin=Reflex.Optimizer #-}

12#endif

13module Reflex.BehaviorWriter.Class

14 ( MonadBehaviorWriter

15 , BehaviorWriter(..)

16 ) where

18import Control.Monad.Reader (ReaderT, lift)

19import Reflex.Class (Behavior)

21{-# DEPRECATED MonadBehaviorWriter "Use 'BehaviorWriter' instead" #-}

22-- | Type synonym for 'BehaviorWriter'

23type MonadBehaviorWriter = BehaviorWriter

25-- | 'BehaviorWriter' efficiently collects 'Behavior' values using 'tellBehavior'

26-- and combines them monoidally to provide a 'Behavior' result.

27class (Monad m, Monoid w) => BehaviorWriter t w m | m -> t w where

28 tellBehavior :: Behavior t w -> m ()

30instance BehaviorWriter t w m => BehaviorWriter t w (ReaderT r m) where

31 tellBehavior = lift . tellBehavior