final revision to GArrow classes

[ghc-base.git] / GHC / Read.lhs

diff --git a/GHC/Read.lhs b/GHC/Read.lhs
index 1a7b6a8..6305276 100644 (file)
--- a/GHC/Read.lhs
+++ b/GHC/Read.lhs
@@ -1,6 +1,7 @@
 \begin{code}
-{-# OPTIONS_GHC -XNoImplicitPrelude #-}
+{-# LANGUAGE CPP, NoImplicitPrelude, StandaloneDeriving #-}
 {-# OPTIONS_HADDOCK hide #-}
+
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  GHC.Read
@@ -71,6 +72,8 @@ import GHC.Float ()
 import GHC.Show
 import GHC.Base
 import GHC.Arr
+-- For defining instances for the generic deriving mechanism
+import GHC.Generics (Arity(..), Associativity(..), Fixity(..))
 \end{code}
 
 
@@ -679,3 +682,10 @@ readp :: Read a => ReadP a
 readp = readPrec_to_P readPrec minPrec
 \end{code}
 
+Instances for types of the generic deriving mechanism.
+
+\begin{code}
+deriving instance Read Arity
+deriving instance Read Associativity
+deriving instance Read Fixity
+\end{code}
\ No newline at end of file