From 8160d55ca73a164aed9540d82ac977c1b7bcd092 Mon Sep 17 00:00:00 2001
From: sof <unknown>
Date: Mon, 24 Nov 1997 20:40:59 +0000
Subject: [PATCH] [project @ 1997-11-24 20:40:59 by sof] Added Read BufferMode
instance
---
ghc/lib/required/IO.lhs | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/ghc/lib/required/IO.lhs b/ghc/lib/required/IO.lhs
index 4e058d3761b2..62345929352a 100644
--- a/ghc/lib/required/IO.lhs
+++ b/ghc/lib/required/IO.lhs
@@ -40,6 +40,7 @@ import ArrBase ( MutableByteArray(..), newCharArray )
import IOHandle -- much of the real stuff is in here
import PackBase ( unpackNBytesST )
import PrelBase
+import PrelRead ( readParen, Read(..), reads, lex )
import PrelMaybe
import PrelEither
import GHC
@@ -129,6 +130,18 @@ instance Show Handle where {showsPrec p h = showString "<<Handle>>"}
instance Eq HandlePosn where
(HandlePosn h1 p1) == (HandlePosn h2 p2) = p1==p2 && h1==h2
+-- Type declared in IOBase, instance here because it
+-- depends on PrelRead.(Read Maybe) instance.
+instance Read BufferMode where
+ readsPrec p =
+ 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}
%*********************************************************
--
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