X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Futils%2FPair.lhs;h=9e847d69505503c18e22034ddf88ff6f92a20e3e;hb=41cecc14547b049cec20e827ceae8ff312c9ff4f;hp=eb594af45f7278899b01e6c463dc24b2cf11554c;hpb=fdf8656855d26105ff36bdd24d41827b05037b91;p=ghc-hetmet.git

diff --git a/compiler/utils/Pair.lhs b/compiler/utils/Pair.lhs
index eb594af..9e847d6 100644
--- a/compiler/utils/Pair.lhs
+++ b/compiler/utils/Pair.lhs
@@ -1,47 +1,47 @@
-
-A simple homogeneous pair type with useful Functor, Applicative, and
-Traversable instances.
-
-\begin{code}
-module Pair ( Pair(..), unPair, toPair, swap ) where
-
-#include "HsVersions.h"
-
-import Outputable
-import Data.Monoid
-import Control.Applicative
-import Data.Foldable
-import Data.Traversable
-
-data Pair a = Pair { pFst :: a, pSnd :: a }
--- Note that Pair is a *unary* type constructor
--- whereas (,) is binary
-
--- The important thing about Pair is that it has a *homogenous*
--- Functor instance, so you can easily apply the same function
--- to both components
-instance Functor Pair where
-  fmap f (Pair x y) = Pair (f x) (f y)
-
-instance Applicative Pair where
-  pure x = Pair x x
-  (Pair f g) <*> (Pair x y) = Pair (f x) (g y)
-
-instance Foldable Pair where
-  foldMap f (Pair x y) = f x `mappend` f y
-
-instance Traversable Pair where
-  traverse f (Pair x y) = Pair <$> f x <*> f y
-
-instance Outputable a => Outputable (Pair a) where
-  ppr (Pair a b) = ppr a <+> char '~' <+> ppr b
-
-unPair :: Pair a -> (a,a)
-unPair (Pair x y) = (x,y)
-
-toPair :: (a,a) -> Pair a
-toPair (x,y) = Pair x y
-
-swap :: Pair a -> Pair a
-swap (Pair x y) = Pair y x
+
+A simple homogeneous pair type with useful Functor, Applicative, and
+Traversable instances.
+
+\begin{code}
+module Pair ( Pair(..), unPair, toPair, swap ) where
+
+#include "HsVersions.h"
+
+import Outputable
+import Data.Monoid
+import Control.Applicative
+import Data.Foldable
+import Data.Traversable
+
+data Pair a = Pair { pFst :: a, pSnd :: a }
+-- Note that Pair is a *unary* type constructor
+-- whereas (,) is binary
+
+-- The important thing about Pair is that it has a *homogenous*
+-- Functor instance, so you can easily apply the same function
+-- to both components
+instance Functor Pair where
+  fmap f (Pair x y) = Pair (f x) (f y)
+
+instance Applicative Pair where
+  pure x = Pair x x
+  (Pair f g) <*> (Pair x y) = Pair (f x) (g y)
+
+instance Foldable Pair where
+  foldMap f (Pair x y) = f x `mappend` f y
+
+instance Traversable Pair where
+  traverse f (Pair x y) = Pair <$> f x <*> f y
+
+instance Outputable a => Outputable (Pair a) where
+  ppr (Pair a b) = ppr a <+> char '~' <+> ppr b
+
+unPair :: Pair a -> (a,a)
+unPair (Pair x y) = (x,y)
+
+toPair :: (a,a) -> Pair a
+toPair (x,y) = Pair x y
+
+swap :: Pair a -> Pair a
+swap (Pair x y) = Pair y x
 \end{code}
\ No newline at end of file