From 2c2943905952c7298b38047f612cdcef2d9e4aa5 Mon Sep 17 00:00:00 2001
From: simonmar <unknown>
Date: Tue, 28 May 2002 14:04:18 +0000
Subject: [PATCH] [project @ 2002-05-28 14:04:18 by simonmar] Fix mistake in
 'evaluate'.

---
 Control/Exception.hs |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Control/Exception.hs b/Control/Exception.hs
index 5231db4..be7595e 100644
--- a/Control/Exception.hs
+++ b/Control/Exception.hs
@@ -223,7 +223,10 @@ handleJust p =  flip (catchJust p)
 --
 -- NOTE: @(evaluate a)@ is /not/ the same as @(a \`seq\` return a)@.
 evaluate :: a -> IO a
-evaluate a = IO $ \s -> a `seq` (# s, a #)
+evaluate a = IO $ \s -> case a `seq` () of () -> (# s, a #)
+	-- NB. can't write  
+	-- 	a `seq` (# s, a #)
+	-- because we can't have an unboxed tuple as a function argument
 
 -----------------------------------------------------------------------------
 -- 'try' and variations.
-- 
1.7.10.4