From: simonpj <unknown>
Date: Mon, 16 Sep 2002 12:45:59 +0000 (+0000)
Subject: [project @ 2002-09-16 12:45:59 by simonpj]
X-Git-Tag: Approx_11550_changesets_converted~1670
X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;ds=sidebyside;h=56200d7c130bb75eb5da930a01f32bb983cc5095;p=ghc-hetmet.git

[project @ 2002-09-16 12:45:59 by simonpj]
Silly bug in plusImportAvails [HEAD only]
---

diff --git a/ghc/compiler/typecheck/TcRnTypes.lhs b/ghc/compiler/typecheck/TcRnTypes.lhs
index db4e7f8..8babf69 100644
--- a/ghc/compiler/typecheck/TcRnTypes.lhs
+++ b/ghc/compiler/typecheck/TcRnTypes.lhs
@@ -478,6 +478,9 @@ data ImportAvails
 		-- Used to figure out "module M" export specifiers
 		-- Domain is only modules with *unqualified* imports
 		-- (see 1.4 Report Section 5.1.1)
+		-- The list of Avails is cumulative, not necessarily
+		-- nicely uniquified. For example, we might have Maybe(Nothing)
+		-- and Maybe(Just) in the list, separately.
 
 	imp_mods :: ModuleEnv (Module, Bool)
 		-- Domain is all directly-imported modules
@@ -502,7 +505,7 @@ plusImportAvails
   (ImportAvails { imp_env = env1, imp_unqual = unqual1, imp_mods = mods1 })
   (ImportAvails { imp_env = env2, imp_unqual = unqual2, imp_mods = mods2 })
   = ImportAvails { imp_env    = env1 `plusAvailEnv` env2, 
-		   imp_unqual = unqual1 `plusModuleEnv` unqual2, 
+		   imp_unqual = plusModuleEnv_C (++) unqual1 unqual2, 
 		   imp_mods   = mods1 `plusModuleEnv` mods2 }
 
 mkImportAvails :: ModuleName -> Bool