Comments only: replace ":=:" by "~" (notation for equality predicates)

[ghc-hetmet.git] / compiler / typecheck / TcSplice.lhs

diff --git a/compiler/typecheck/TcSplice.lhs b/compiler/typecheck/TcSplice.lhs
index 60d6a6b..b4cb316 100644 (file)
--- a/compiler/typecheck/TcSplice.lhs
+++ b/compiler/typecheck/TcSplice.lhs
@@ -63,13 +63,14 @@ import Maybe
 import BasicTypes
 import Panic
 import FastString
+import Exception
 
 import qualified Language.Haskell.TH as TH
 -- THSyntax gives access to internal functions and data types
 import qualified Language.Haskell.TH.Syntax as TH
 
 import GHC.Exts                ( unsafeCoerce#, Int#, Int(..) )
-import qualified Control.Exception  as Exception( userErrors )
+import System.IO.Error
 \end{code}
 
 Note [Template Haskell levels]
@@ -593,10 +594,11 @@ runMeta convert expr
 
        ; case either_tval of
            Right v -> return v
-           Left exn | Just s <- Exception.userErrors exn
-                    , s == "IOEnv failure" 
-                    -> failM   -- Error already in Tc monad
-                    | otherwise -> failWithTc (mk_msg "run" exn)       -- Exception
+           Left se ->
+                    case fromException se of
+                    Just IOEnvFailure ->
+                        failM -- Error already in Tc monad
+                    _ -> failWithTc (mk_msg "run" se)  -- Exception
         }}}
   where
     mk_msg s exn = vcat [text "Exception when trying to" <+> text s <+> text "compile-time code:",
@@ -625,11 +627,10 @@ like that.  Here's how it's processed:
 
   * The TcM monad is an instance of Quasi (see TcSplice), and it implements
     (qReport True s) by using addErr to add an error message to the bag of errors.
-    The 'fail' in TcM raises a UserError, with the uninteresting string
-       "IOEnv failure"
+    The 'fail' in TcM raises an IOEnvFailure exception
 
   * So, when running a splice, we catch all exceptions; then for 
-       - a UserError "IOEnv failure", we assume the error is already 
+       - an IOEnvFailure exception, we assume the error is already 
                in the error-bag (above)
        - other errors, we add an error to the bag
     and then fail
@@ -920,7 +921,7 @@ reifyName thing
        -- have free variables, we may need to generate NameL's for them.
   where
     name    = getName thing
-    mod     = nameModule name
+    mod     = ASSERT( isExternalName name ) nameModule name
     pkg_str = packageIdString (modulePackageId mod)
     mod_str = moduleNameString (moduleName mod)
     occ_str = occNameString occ