"Fix" existing unused monadic result warnings by adding _ <-

They all look dubious and should be reviewed properly

Network/HTTP/HandleStream.hs

@@ -1,4 +1,3 @@
-{-# OPTIONS_GHC -fno-warn-unused-do-bind #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Network.HTTP.HandleStream
@@ -114,9 +113,11 @@ sendMain conn rqst onSendComplete = do
       --let str = if null (rqBody rqst)
       --              then show rqst
       --              else show (insertHeader HdrExpect "100-continue" rqst)
-  writeBlock conn (buf_fromStr bufferOps $ show rqst)
+  -- TODO review throwing away of result
+  _ <- writeBlock conn (buf_fromStr bufferOps $ show rqst)
     -- write body immediately, don't wait for 100 CONTINUE
-  writeBlock conn (rqBody rqst)
+  -- TODO review throwing away of result
+  _ <- writeBlock conn (rqBody rqst)
   onSendComplete
   rsp <- getResponseHead conn
   switchResponse conn True False rsp rqst
@@ -152,7 +153,8 @@ switchResponse conn allow_retry bdy_sent (Right (cd,rn,hdrs)) rqst =
      Retry -> do {- Request with "Expect" header failed.
                     Trouble is the request contains Expects
                     other than "100-Continue" -}
-        writeBlock conn ((buf_append bufferOps)
+        -- TODO review throwing away of result
+        _ <- writeBlock conn ((buf_append bufferOps)
 		                     (buf_fromStr bufferOps (show rqst))
 			             (rqBody rqst))
         rsp <- getResponseHead conn
@@ -230,9 +232,11 @@ receiveHTTP conn = getRequestHead >>= either (return . Left) processRequest
 -- server interactions, performing the dual role to 'sendHTTP'.
 respondHTTP :: HStream ty => HandleStream ty -> Response ty -> IO ()
 respondHTTP conn rsp = do 
-  writeBlock conn (buf_fromStr bufferOps $ show rsp)
+  -- TODO: review throwing away of result
+  _ <- writeBlock conn (buf_fromStr bufferOps $ show rsp)
    -- write body immediately, don't wait for 100 CONTINUE
-  writeBlock conn (rspBody rsp)
+  -- TODO: review throwing away of result
+  _ <- writeBlock conn (rspBody rsp)
   return ()
 
 ------------------------------------------------------------------------------

Network/HTTP/Proxy.hs

@@ -1,4 +1,3 @@
-{-# OPTIONS_GHC -fno-warn-unused-do-bind #-}
 {-# LANGUAGE CPP #-}
 -----------------------------------------------------------------------------
 -- |
@@ -165,7 +164,9 @@ uri2proxy _ = Nothing
 #if defined(WIN32)
 regQueryValueDWORD :: HKEY -> String -> IO DWORD
 regQueryValueDWORD hkey name = alloca $ \ptr -> do
-  regQueryValueEx hkey name (castPtr ptr) (sizeOf (undefined :: DWORD))
+  -- TODO: this throws away the key type returned by regQueryValueEx
+  -- we should check it's what we expect instead
+  _ <- regQueryValueEx hkey name (castPtr ptr) (sizeOf (undefined :: DWORD))
   peek ptr
 
 #endif

Network/HTTP/Stream.hs

@@ -1,4 +1,3 @@
-{-# OPTIONS_GHC -fno-warn-unused-do-bind #-}
 -----------------------------------------------------------------------------
 -- |
 -- Module      :  Network.HTTP.Stream
@@ -108,9 +107,11 @@ sendMain conn rqst onSendComplete =  do
     --let str = if null (rqBody rqst)
     --              then show rqst
     --              else show (insertHeader HdrExpect "100-continue" rqst)
-   writeBlock conn (show rqst)
+    -- TODO review throwing away of result
+   _ <- writeBlock conn (show rqst)
     -- write body immediately, don't wait for 100 CONTINUE
-   writeBlock conn (rqBody rqst)
+   -- TODO review throwing away of result
+   _ <- writeBlock conn (rqBody rqst)
    onSendComplete
    rsp <- getResponseHead conn
    switchResponse conn True False rsp rqst
@@ -155,7 +156,8 @@ switchResponse conn allow_retry bdy_sent (Right (cd,rn,hdrs)) rqst =
                 Retry -> {- Request with "Expect" header failed.
                                 Trouble is the request contains Expects
                                 other than "100-Continue" -}
-                    do { writeBlock conn (show rqst ++ rqBody rqst)
+                    do { -- TODO review throwing away of result
+                         _ <- writeBlock conn (show rqst ++ rqBody rqst)
                        ; rsp <- getResponseHead conn
                        ; switchResponse conn False bdy_sent rsp rqst
                        }   
@@ -226,7 +228,9 @@ receiveHTTP conn = getRequestHead >>= processRequest
 -- | Very simple function, send a HTTP response over the given stream. This 
 --   could be improved on to use different transfer types.
 respondHTTP :: Stream s => s -> Response_String -> IO ()
-respondHTTP conn rsp = do writeBlock conn (show rsp)
+respondHTTP conn rsp = do -- TODO review throwing away of result
+                          _ <- writeBlock conn (show rsp)
                           -- write body immediately, don't wait for 100 CONTINUE
-                          writeBlock conn (rspBody rsp)
+                          -- TODO review throwing away of result
+                          _ <- writeBlock conn (rspBody rsp)
 			  return ()