Foldable ResourceNode

[Lucu.git] / Network / HTTP / Lucu / Dispatcher / Internal.hs

diff --git a/Network/HTTP/Lucu/Dispatcher/Internal.hs b/Network/HTTP/Lucu/Dispatcher/Internal.hs
index 71e5ffd211659b6af3dc8019b6db3f92e3c17eea..f86eb1f4dacecf75bc5ef663e217b7828d208481 100644 (file)
--- a/Network/HTTP/Lucu/Dispatcher/Internal.hs
+++ b/Network/HTTP/Lucu/Dispatcher/Internal.hs
@@ -2,10 +2,12 @@
     DoAndIfThenElse
   , ExistentialQuantification
   , FlexibleInstances
+  , GeneralizedNewtypeDeriving
   , OverlappingInstances
   , MultiParamTypeClasses
   , RecordWildCards
   , ScopedTypeVariables
+  , TemplateHaskell
   , UndecidableInstances
   , UnicodeSyntax
   #-}
@@ -17,7 +19,6 @@ module Network.HTTP.Lucu.Dispatcher.Internal
     , ResourceMapper(..)
     , ResourceMap
     , ResourceTree
-    , ResourceNode
 
     , dispatch
     )
@@ -26,13 +27,14 @@ import Control.Applicative hiding (empty)
 import Control.Monad.Trans.Maybe
 import Control.Monad.Unicode
 import Data.Collections
-import qualified Data.Map as M
+import qualified Data.Collections.Newtype.TH as C
 import Data.Monoid
 import Data.Monoid.Unicode
+import Network.HTTP.Lucu.Dispatcher.Node
 import Network.HTTP.Lucu.Resource.Internal
 import Network.HTTP.Lucu.Utils
 import Network.URI hiding (path)
-import Prelude hiding (filter, lookup, null)
+import Prelude hiding (lookup)
 import Prelude.Unicode
 
 -- |FIXME: docs
@@ -73,15 +75,7 @@ data ResourceMap = ∀α. ResourceMapper α ⇒ RMap α
 
 -- FIXME: doc
 newtype ResourceTree = Root ResourceNode
-
--- FIXME: docs
-data ResourceNode
-    = Greedy    !Resource
-    | NonGreedy !Resource !SubTree
-    | Branch              !SubTree
-
-type SubTree
-    = M.Map PathSegment ResourceNode
+    deriving (Monoid, Show)
 
 -- Instances of SchemeMapper --------------------------------------------------
 instance SchemeMapper SchemeMap where
@@ -242,50 +236,8 @@ instance ResourceMapper (PathSegments → Maybe (PathSegments, Resource)) where
     findResource = (maybe (fail (⊥)) return ∘) ∘ flip id
 
 -- Instances of ResourceTree --------------------------------------------------
-instance Unfoldable ResourceTree (PathSegments, ResourceNode) where
-    {-# INLINE insert #-}
-    insert e (Root root) = Root $ insert e root
-    {-# INLINE empty #-}
-    empty = (∅)
-
-instance Monoid ResourceTree where
-    {-# INLINE mempty #-}
-    mempty = Root (∅)
-    {-# INLINE mappend #-}
-    mappend (Root a) (Root b)
-        = Root (a ⊕ b)
-
--- Instances of ResourceNode --------------------------------------------------
-instance Unfoldable ResourceNode (PathSegments, ResourceNode) where
-    {-# INLINEABLE insert #-}
-    insert (p, n) = insertNodeAt (canonPath p) n
-    {-# INLINE empty #-}
-    empty = Branch (∅)
-
-canonPath ∷ (Collection c f, Foldable f e) ⇒ c → c
-{-# INLINEABLE canonPath #-}
-canonPath = filter ((¬) ∘ null)
-
-insertNodeAt ∷ PathSegments → ResourceNode → ResourceNode → ResourceNode
-{-# INLINEABLE insertNodeAt #-}
-insertNodeAt p a b
-    = case front p of
-        Nothing         → a ⊕ b
-        Just (x, xs)
-            | null xs   → Branch (singleton (x, a)) ⊕ b
-            | otherwise → insertNodeAt xs a (∅) ⊕ b
-
-instance Monoid ResourceNode where
-    {-# INLINE mempty #-}
-    mempty = Branch (∅)
-    {-# INLINEABLE mappend #-}
-    mappend _               (Greedy    r  ) = Greedy    r
-    mappend (Greedy    _  ) (NonGreedy r n) = NonGreedy r      n
-    mappend (NonGreedy _ m) (NonGreedy r n) = NonGreedy r (m ⊕ n)
-    mappend (Branch      m) (NonGreedy r n) = NonGreedy r (m ⊕ n)
-    mappend (Greedy    r  ) (Branch      _) = Greedy    r
-    mappend (NonGreedy r m) (Branch      n) = NonGreedy r (m ⊕ n)
-    mappend (Branch      m) (Branch      n) = Branch      (m ⊕ n)
+C.derive [d| instance Foldable ResourceTree (PathSegments, ResourceNode)
+           |]
 
 -- dispatch -------------------------------------------------------------------
 dispatch ∷ SchemeMapper α ⇒ URI → α → MaybeT IO (PathSegments, Resource)