From 834e82079c32fa24eb6e0beb6f202add9379dc49 Mon Sep 17 00:00:00 2001
From: simonmar <unknown>
Date: Thu, 14 Jul 2005 15:14:33 +0000
Subject: [PATCH] [project @ 2005-07-14 15:14:33 by simonmar] - -package P
 picks the latest version of P, instead of complaining    
 if P is ambiguous.

  - -hide-package P hides all versions of P, instead of complaining
    if P is ambiguous.
---
 ghc/compiler/main/Packages.lhs |   31 ++++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/ghc/compiler/main/Packages.lhs b/ghc/compiler/main/Packages.lhs
index 6f0b867..79fd2d0 100644
--- a/ghc/compiler/main/Packages.lhs
+++ b/ghc/compiler/main/Packages.lhs
@@ -66,7 +66,7 @@ import Distribution.Version
 import Data.Maybe	( isNothing )
 import System.Directory	( doesFileExist )
 import Control.Monad	( foldM )
-import Data.List	( nub, partition )
+import Data.List	( nub, partition, sortBy )
 
 #ifdef mingw32_TARGET_OS
 import Data.List	( isPrefixOf )
@@ -289,20 +289,18 @@ mkPackageState dflags orig_pkg_db = do
 
 	procflags pkgs expl [] = return (pkgs,expl)
 	procflags pkgs expl (ExposePackage str : flags) = do
-	   case partition (matches str) pkgs of
-		([],_)   -> missingPackageErr str
-		([p],ps) -> procflags (p':ps') expl' flags
+	   case pick str pkgs of
+		Nothing -> missingPackageErr str
+		Just (p,ps) -> procflags (p':ps') expl' flags
 		  where pkgid = packageConfigId p
 			p' = p {exposed=True}
 		        ps' = hideAll (pkgName (package p)) ps
 			expl' = addOneToUniqSet expl pkgid
-		(ps,_)   -> multiplePackagesErr str ps
 	procflags pkgs expl (HidePackage str : flags) = do
 	   case partition (matches str) pkgs of
 		([],_)   -> missingPackageErr str
-		([p],ps) -> procflags (p':ps) expl flags
-		  where p' = p {exposed=False}
-		(ps,_)   -> multiplePackagesErr str ps
+		(ps,qs) -> procflags (map hide ps ++ qs) expl flags
+		  where hide p = p {exposed=False}
 	procflags pkgs expl (IgnorePackage str : flags) = do
 	   case partition (matches str) pkgs of
 		(ps,qs) -> procflags qs expl flags
@@ -310,6 +308,16 @@ mkPackageState dflags orig_pkg_db = do
 		-- because a common usage is to -ignore-package P as
 		-- a preventative measure just in case P exists.
 
+	pick str pkgs
+	  = case partition (matches str) pkgs of
+		([],_) -> Nothing
+		(ps,rest) -> 
+		   case sortBy (flip (comparing (pkgVersion.package))) ps of
+			(p:ps) -> Just (p, ps ++ rest)
+			_ -> panic "Packages.pick"
+
+        comparing f a b = f a `compare` f b
+
 	-- A package named on the command line can either include the
 	-- version, or just the name if it is unambiguous.
 	matches str p
@@ -413,13 +421,6 @@ haskell98PackageName = FSLIT("haskell98")
 thPackageName        = FSLIT("template-haskell")
 				-- Template Haskell libraries in here
 
-multiplePackagesErr str ps =
-  throwDyn (CmdLineError (showSDoc (
-		   text "Error; multiple packages match" <+> 
-			text str <> colon <+>
-		    sep (punctuate comma (map (text.showPackageId.package) ps))
-		)))
-
 mkModuleMap
   :: PackageConfigMap
   -> [PackageId]
-- 
1.7.10.4