[project @ 2002-05-09 13:16:29 by simonmar]

[ghc-base.git] / Foreign / Marshal / Error.hs

diff --git a/Foreign/Marshal/Error.hs b/Foreign/Marshal/Error.hs
index c896ce2..46fa2b7 100644 (file)
--- a/Foreign/Marshal/Error.hs
+++ b/Foreign/Marshal/Error.hs
@@ -1,23 +1,22 @@
 {-# OPTIONS -fno-implicit-prelude #-}
 -----------------------------------------------------------------------------
--- 
+-- |
 -- Module      :  Foreign.Marshal.Error
 -- Copyright   :  (c) The FFI task force 2001
--- License     :  BSD-style (see the file libraries/core/LICENSE)
+-- License     :  BSD-style (see the file libraries/base/LICENSE)
 -- 
 -- Maintainer  :  ffi@haskell.org
--- Stability   :  experimental
--- Portability :  non-portable
---
--- $Id: Error.hs,v 1.1 2001/06/28 14:15:03 simonmar Exp $
+-- Stability   :  provisional
+-- Portability :  portable
 --
 -- Marshalling support: Handling of common error conditions
 --
 -----------------------------------------------------------------------------
 
 module Foreign.Marshal.Error (
+  -- * Error utilities
 
-  -- throw an exception on specific return values
+  -- |Throw an exception on specific return values
   --
   throwIf,       -- :: (a -> Bool) -> (a -> String) -> IO a       -> IO a
   throwIf_,      -- :: (a -> Bool) -> (a -> String) -> IO a       -> IO ()
@@ -27,7 +26,7 @@ module Foreign.Marshal.Error (
                 -- =>                (a -> String) -> IO a       -> IO ()
   throwIfNull,   -- ::                String        -> IO (Ptr a) -> IO (Ptr a)
 
-  -- discard return value
+  -- Discard return value
   --
   void           -- IO a -> IO ()
 ) where
@@ -43,10 +42,10 @@ import GHC.IOBase
 -- exported functions
 -- ------------------
 
--- guard an IO operation and throw an exception if the result meets the given
+-- |Guard an 'IO' operation and throw an exception if the result meets the given
 -- predicate 
 --
--- * the second argument computes an error message from the result of the IO
+-- * the second argument computes an error message from the result of the 'IO'
 --   operation
 --
 throwIf                 :: (a -> Bool) -> (a -> String) -> IO a -> IO a
@@ -55,27 +54,27 @@ throwIf pred msgfct act  =
     res <- act
     (if pred res then ioError . userError . msgfct else return) res
 
--- like `throwIf', but discarding the result
+-- |Like 'throwIf', but discarding the result
 --
 throwIf_                 :: (a -> Bool) -> (a -> String) -> IO a -> IO ()
 throwIf_ pred msgfct act  = void $ throwIf pred msgfct act
 
--- guards against negative result values
+-- |Guards against negative result values
 --
 throwIfNeg :: (Ord a, Num a) => (a -> String) -> IO a -> IO a
 throwIfNeg  = throwIf (< 0)
 
--- like `throwIfNeg', but discarding the result
+-- |Like 'throwIfNeg', but discarding the result
 --
 throwIfNeg_ :: (Ord a, Num a) => (a -> String) -> IO a -> IO ()
 throwIfNeg_  = throwIf_ (< 0)
 
--- guards against null pointers
+-- |Guards against null pointers
 --
 throwIfNull :: String -> IO (Ptr a) -> IO (Ptr a)
 throwIfNull  = throwIf (== nullPtr) . const
 
--- discard the return value of an IO action
+-- |Discard the return value of an 'IO' action
 --
 void     :: IO a -> IO ()
 void act  = act >> return ()