From: Ian Lynagh <igloo@earth.li>
Date: Thu, 24 Jan 2008 15:58:27 +0000 (+0000)
Subject: Make the Parser Monad's return strict
X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=commitdiff_plain;h=0c3e42b73205ec0811ab1899fa60bfdebd4ae77d

Make the Parser Monad's return strict
---

diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x
index 2aa8f4f..8d2a9a5 100644
--- a/compiler/parser/Lexer.x
+++ b/compiler/parser/Lexer.x
@@ -1410,7 +1410,7 @@ instance Monad P where
   fail = failP
 
 returnP :: a -> P a
-returnP a = P $ \s -> POk s a
+returnP a = a `seq` (P $ \s -> POk s a)
 
 thenP :: P a -> (a -> P b) -> P b
 (P m) `thenP` k = P $ \ s ->