[project @ 2001-05-22 19:25:49 by qrczak]

Remove module dependency loop: don't import PrelIOBase in PrelRead.
readIO is in PrelIO, remove it from PrelRead. Derive instance Read
BufferMode automatically.

diff --git a/ghc/lib/std/PrelIOBase.lhs b/ghc/lib/std/PrelIOBase.lhs
index 918d3ed..351f271 100644 (file)
--- a/ghc/lib/std/PrelIOBase.lhs
+++ b/ghc/lib/std/PrelIOBase.lhs
@@ -1,5 +1,5 @@
 % ------------------------------------------------------------------------------
-% $Id: PrelIOBase.lhs,v 1.39 2001/05/22 15:06:47 simonmar Exp $
+% $Id: PrelIOBase.lhs,v 1.40 2001/05/22 19:25:49 qrczak Exp $
 % 
 % (c) The University of Glasgow, 1994-2001
 %
@@ -14,13 +14,13 @@
 module PrelIOBase where
 
 import PrelST
-import PrelRead
 import PrelArr
 import PrelBase
 import PrelNum -- To get fromInteger etc, needed because of -fno-implicit-prelude
 import PrelMaybe  ( Maybe(..) )
 import PrelShow
 import PrelList
+import PrelRead
 import PrelDynamic
 
 -- ---------------------------------------------------------------------------
@@ -219,7 +219,6 @@ bufferIsWritable _other = False
 
 bufferEmpty :: Buffer -> Bool
 bufferEmpty Buffer{ bufRPtr=r, bufWPtr=w } = r == w
-bufferEmpty _other = False
 
 -- only makes sense for a write buffer
 bufferFull :: Buffer -> Bool
@@ -284,7 +283,7 @@ type FilePath = String
 
 data BufferMode  
  = NoBuffering | LineBuffering | BlockBuffering (Maybe Int)
-   deriving (Eq, Ord, Show, Read)
+   deriving (Eq, Ord, Read, Show)
 
 -- ---------------------------------------------------------------------------
 -- IORefs

diff --git a/ghc/lib/std/PrelRead.lhs b/ghc/lib/std/PrelRead.lhs
index 995b9e6..67a8194 100644 (file)
--- a/ghc/lib/std/PrelRead.lhs
+++ b/ghc/lib/std/PrelRead.lhs
@@ -1,5 +1,5 @@
 % ------------------------------------------------------------------------------
-% $Id: PrelRead.lhs,v 1.18 2001/02/28 00:01:03 qrczak Exp $
+% $Id: PrelRead.lhs,v 1.19 2001/05/22 19:25:49 qrczak Exp $
 %
 % (c) The University of Glasgow, 1994-2000
 %
@@ -13,7 +13,7 @@ Instances of the Read class.
 
 module PrelRead where
 
-import PrelErr         ( error )
+import {-# SOURCE #-} PrelErr          ( error )
 import PrelEnum                ( Enum(..), maxBound )
 import PrelNum
 import PrelReal
@@ -24,8 +24,8 @@ import PrelShow               -- isAlpha etc
 import PrelBase
 
 -- needed for readIO and instance Read Buffermode
-import PrelIOBase ( IO, userError, BufferMode(..) )
-import PrelException ( ioError )
+--import PrelIOBase ( IO, userError, BufferMode(..) )
+--import PrelException ( ioError )
 \end{code}
 
 %*********************************************************
@@ -101,19 +101,6 @@ read s          =
     (x,str1) <- reads str
     ("","")  <- lex str1
     return x
-
-  -- raises an exception instead of an error
-readIO          :: Read a => String -> IO a
-readIO s        =  case (do { (x,t) <- reads s ; ("","") <- lex t ; return x }) of
-#ifndef NEW_READS_REP
-                       [x]    -> return x
-                       []     -> ioError (userError "Prelude.readIO: no parse")
-                       _      -> ioError (userError "Prelude.readIO: ambiguous parse")
-#else
-                        Just x -> return x
-                        Nothing  -> ioError (userError "Prelude.readIO: no parse")
-#endif
-
 \end{code}
 
 \begin{code}
@@ -623,26 +610,3 @@ readRational__ top_s
 #endif
 
 \end{code}
-
-%*********************************************************
-%*                                                     *
-\subsection{Reading BufferMode}
-%*                                                     *
-%*********************************************************
-
-This instance decl is here rather than somewhere more appropriate in
-order that we can avoid both orphan-instance modules and recursive
-dependencies.
-
-\begin{code}
-instance Read BufferMode where
-    readsPrec _ = 
-      readParen False
-       (\r ->  let lr = lex r
-               in
-               [(NoBuffering, rest)       | ("NoBuffering", rest) <- lr] ++
-               [(LineBuffering,rest)      | ("LineBuffering",rest) <- lr] ++
-               [(BlockBuffering mb,rest2) | ("BlockBuffering",rest1) <- lr,
-                                            (mb, rest2) <- reads rest1])
-
-\end{code}