machines 0.1 → 0.1.1

raw patch · 2 files changed

+64/−1 lines, 2 filesdep ~base

Dependency ranges changed: base

Files

• machines.cabal +2/−1
• src/Data/Machine/Source.hs +62/−0

@@ -1,6 +1,6 @@ name:          machines category:      Control, Enumerator-version:       0.1+version:       0.1.1 license:       BSD3 cabal-version: >= 1.10 license-file:  LICENSE@@ -45,6 +45,7 @@     Data.Machine.Moore     Data.Machine.Process     Data.Machine.Plan+    Data.Machine.Source     Data.Machine.Tee     Data.Machine.Type     Data.Machine.Unread

@@ -0,0 +1,62 @@+{-# LANGUAGE Rank2Types #-}+{-# LANGUAGE FlexibleInstances #-}+-----------------------------------------------------------------------------+-- |+-- Module      :  Data.Machine.Source+-- Copyright   :  (C) 2012 Edward Kmett+-- License     :  BSD-style (see the file LICENSE)+--+-- Maintainer  :  Edward Kmett <ekmett@gmail.com>+-- Stability   :  provisional+-- Portability :  Rank-2 Types+--+----------------------------------------------------------------------------+module Data.Machine.Source+  (+  -- * Sources+    Source, SourceT+  , source+  , repeated+  , cycled+  , cap+  ) where++import Control.Category+import Data.Foldable+import Data.Machine.Plan+import Data.Machine.Type+import Data.Machine.Process+import Prelude hiding ((.),id)++-------------------------------------------------------------------------------+-- Source+-------------------------------------------------------------------------------++-- | A 'Source' never reads from its inputs.+type Source b = forall k a. Machine k a b++-- | A 'SourceT' never reads from its inputs, but may have monadic side-effects.+type SourceT m b = forall k a. MachineT m k a b++-- | Repeat the same value, over and over.+repeated :: o -> Source o+repeated = repeatedly . yield++-- | Loop through a 'Foldable' container over and over.+cycled :: Foldable f => f b -> Source b+cycled xs = repeatedly (traverse_ yield xs)++-- | Generate a 'Source' from any 'Foldable' container.+source :: Foldable f => f b -> Source b+source xs = construct (traverse_ yield xs)++-- |+-- You can transform a 'Source' with a 'Process'.+--+-- Alternately you can view this as capping the 'Source' end of a 'Process',+-- yielding a new 'Source'.+--+-- @'cap' = 'pipe'@+--+cap :: Process a b -> Source a -> Source b+cap l r = after r l