X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Flib%2Fstd%2FPrelRead.lhs;h=ad3fe8161c577fe8b228b535b5c4b57a03aa087f;hb=e921b2e307532e0f30eefa88b11a124be592bde4;hp=596b0c75a8148f269e488068455a0904b36ccbdf;hpb=c415cd35368f45739132fc180837fc07f0490921;p=ghc-hetmet.git

diff --git a/ghc/lib/std/PrelRead.lhs b/ghc/lib/std/PrelRead.lhs
index 596b0c7..ad3fe81 100644
--- a/ghc/lib/std/PrelRead.lhs
+++ b/ghc/lib/std/PrelRead.lhs
@@ -14,7 +14,8 @@ module PrelRead where
 import PrelErr		( error )
 import PrelEnum		( Enum(..) )
 import PrelNum
-import PrelNumExtra
+import PrelReal
+import PrelFloat
 import PrelList
 import PrelTup
 import PrelMaybe
@@ -22,8 +23,8 @@ import PrelShow		-- isAlpha etc
 import PrelBase
 import Monad
 
--- needed for readIO.
-import PrelIOBase ( IO, userError )
+-- needed for readIO and instance Read Buffermode
+import PrelIOBase ( IO, userError, BufferMode(..) )
 import PrelException ( ioError )
 \end{code}
 
@@ -604,3 +605,26 @@ 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}