[project @ 2003-08-30 22:55:42 by ross]

[ghc-base.git] / System / Environment.hs

diff --git a/System/Environment.hs b/System/Environment.hs
index c1b33b0..a0761d5 100644 (file)
--- a/System/Environment.hs
+++ b/System/Environment.hs
@@ -33,6 +33,7 @@ import Foreign
 import Foreign.C
 import Control.Monad
 import GHC.IOBase
+#include "config.h"
 #endif
 
 #ifdef __HUGS__
@@ -50,7 +51,7 @@ import System
 -- ---------------------------------------------------------------------------
 -- getArgs, getProgName, getEnv
 
--- Computation `getArgs' returns a list of the program's command
+-- | Computation 'getArgs' returns a list of the program's command
 -- line arguments (not including the program name).
 
 #ifdef __GLASGOW_HASKELL__
@@ -106,11 +107,13 @@ unpackProgName argv = do
    isPathSeparator _    = False
 
 
--- Computation `getEnv var' returns the value
--- of the environment variable {\em var}.  
-
--- This computation may fail with
---    NoSuchThing: The environment variable does not exist.
+-- | Computation 'getEnv' @var@ returns the value
+-- of the environment variable @var@.  
+--
+-- This computation may fail with:
+--
+--  * 'System.IO.Error.isDoesNotExistError' if the environment variable
+--    does not exist.
 
 getEnv :: String -> IO String
 getEnv name =
@@ -126,15 +129,18 @@ foreign import ccall unsafe "getenv"
 
 {-|
 @withArgs args act@ - while executing action @act@, have 'System.getArgs'
-return @args@.
+return @args@ (GHC only).
 -}
+withArgs :: [String] -> IO a -> IO a
 withArgs xs act = do
    p <- System.Environment.getProgName
    withArgv (p:xs) act
 
 {-|
-@withProgName name act@ - while executing action @act@, have 'System.getProgName'return @name@.
+@withProgName name act@ - while executing action @act@,
+have 'System.getProgName' return @name@ (GHC only).
 -}
+withProgName :: String -> IO a -> IO a
 withProgName nm act = do
    xs <- System.Environment.getArgs
    withArgv (nm:xs) act
@@ -142,6 +148,7 @@ withProgName nm act = do
 -- Worker routine which marshals and replaces an argv vector for
 -- the duration of an action.
 
+withArgv :: [String] -> IO a -> IO a
 withArgv new_args act = do
   pName <- System.Environment.getProgName
   existing_args <- System.Environment.getArgs