[project @ 2005-04-04 10:55:38 by simonmar]

[ghc-hetmet.git] / ghc / compiler / utils / Util.lhs

diff --git a/ghc/compiler/utils/Util.lhs b/ghc/compiler/utils/Util.lhs
index d51a09d..2f20226 100644 (file)
--- a/ghc/compiler/utils/Util.lhs
+++ b/ghc/compiler/utils/Util.lhs
@@ -56,6 +56,7 @@ module Util (
        -- IO-ish utilities
        createDirectoryHierarchy,
        doesDirNameExist,
+       modificationTimeIfExists,
 
        later, handleDyn, handle,
 
@@ -89,10 +90,12 @@ import List         ( zipWith4 )
 #endif
 
 import Monad           ( when )
-import IO              ( catch )
+import IO              ( catch, isDoesNotExistError )
 import Directory       ( doesDirectoryExist, createDirectory )
 import Char            ( isUpper, isAlphaNum, isSpace, ord, isDigit )
 import Ratio           ( (%) )
+import Time            ( ClockTime )
+import Directory       ( getModificationTime )
 
 infixr 9 `thenCmp`
 \end{code}
@@ -840,6 +843,16 @@ handle h f = f `Exception.catch` \e -> case e of
 #endif
 
 -- --------------------------------------------------------------
+-- check existence & modification time at the same time
+
+modificationTimeIfExists :: FilePath -> IO (Maybe ClockTime)
+modificationTimeIfExists f = do
+  (do t <- getModificationTime f; return (Just t))
+       `IO.catch` \e -> if isDoesNotExistError e 
+                       then return Nothing 
+                       else ioError e
+
+-- --------------------------------------------------------------
 -- Filename manipulation
                
 type Suffix = String