From e97817e947520c40c9520618c5d5d56747e4c0f1 Mon Sep 17 00:00:00 2001
From: Alberto Ruiz <aruiz@um.es>
Date: Thu, 24 Apr 2014 13:41:07 +0200
Subject: build with bidirectional type inference

---
 lib/Numeric/Container.hs     | 14 +++++++++-
 lib/Numeric/ContainerBoot.hs | 62 --------------------------------------------
 2 files changed, 13 insertions(+), 63 deletions(-)

diff --git a/lib/Numeric/Container.hs b/lib/Numeric/Container.hs
index a31acfe..46c2903 100644
--- a/lib/Numeric/Container.hs
+++ b/lib/Numeric/Container.hs
@@ -28,7 +28,7 @@
 module Numeric.Container (
     -- * Basic functions
     module Data.Packed,
-    konst, -- build,
+    konst, build,
     constant, linspace,
     diag, ident,
     ctrans,
@@ -188,3 +188,15 @@ instance Container Vector e => Konst e (Int,Int) Matrix
   where
     konst = konst'
 
+class Build d f c e | d -> c, c -> d, f -> e, f -> d, f -> c, c e -> f, d e -> f
+  where
+    build :: d -> f -> c e
+
+instance Container Vector e => Build Int (e -> e) Vector e
+  where
+    build = build'
+
+instance Container Matrix e => Build (Int,Int) (e -> e -> e) Matrix e
+  where
+    build = build'
+
diff --git a/lib/Numeric/ContainerBoot.hs b/lib/Numeric/ContainerBoot.hs
index 8707473..d61633e 100644
--- a/lib/Numeric/ContainerBoot.hs
+++ b/lib/Numeric/ContainerBoot.hs
@@ -502,47 +502,6 @@ type instance ElementOf (Vector a) = a
 type instance ElementOf (Matrix a) = a
 
 ------------------------------------------------------------
-{-
-class Build f where
-    build' :: BoundsOf f -> f -> ContainerOf f
-
-
-#if MIN_VERSION_base(4,7,0)
--- ghc >= 7.7 considers:
---
--- > a -> a
--- > b -> b -> b
---
--- to overlap
-type family BoundsOf x where
-    BoundsOf (a -> a) = Int
-    BoundsOf (a->a->a) = (Int,Int)
-type family ContainerOf x where
-    ContainerOf (a->a) = Vector a
-    ContainerOf (a->a->a) = Matrix a
-#else
-type family BoundsOf x
-type family ContainerOf x
-type instance BoundsOf (a->a) = Int
-type instance BoundsOf (a->a->a) = (Int,Int)
-type instance ContainerOf (a->a) = Vector a
-type instance ContainerOf (a->a->a) = Matrix a
-#endif
-
-
-instance (Element a, Num a) => Build (a->a) where
-    build' = buildV
-
-instance (Element a,
-#if MIN_VERSION_base(4,7,0)
-        BoundsOf (a -> a -> a) ~ (Int,Int),
-        ContainerOf (a -> a -> a) ~ Matrix a,
-#endif
-        Num a)
-        => Build (a->a->a) where
-    build' = buildM
-
--}
 
 buildM (rc,cc) f = fromLists [ [f r c | c <- cs] | r <- rs ]
     where rs = map fromIntegral [0 .. (rc-1)]
@@ -551,27 +510,6 @@ buildM (rc,cc) f = fromLists [ [f r c | c <- cs] | r <- rs ]
 buildV n f = fromList [f k | k <- ks]
     where ks = map fromIntegral [0 .. (n-1)]
 
-{-
-
-----------------------------------------------------
--- experimental
-
-class Konst s where
-    konst' :: Element e => e -> s -> ContainerOf' s e
-
-type family ContainerOf' x y
-
-type instance ContainerOf' Int a = Vector a
-type instance ContainerOf' (Int,Int) a = Matrix a
-
-instance Konst Int where
-    konst' = constantD
-
-instance Konst (Int,Int) where
-    konst' k (r,c) = reshape c $ konst' k (r*c)
-
--}
-
 --------------------------------------------------------
 -- | conjugate transpose
 ctrans :: (Container Vector e, Element e) => Matrix e -> Matrix e
-- 
cgit v1.2.3