diff --git a/src/Convert.hs b/src/Convert.hs
index ae5232d..4bbdc0d 100644
--- a/src/Convert.hs
+++ b/src/Convert.hs
@@ -19,7 +19,7 @@ import qualified Convert.Interface
 import qualified Convert.KWArgs
 import qualified Convert.Logic
 import qualified Convert.NamedBlock
-import qualified Convert.NestTF
+import qualified Convert.NestPI
 import qualified Convert.PackedArray
 import qualified Convert.Return
 import qualified Convert.StarPort
@@ -29,7 +29,7 @@ import qualified Convert.Typedef
 import qualified Convert.UnbasedUnsized
 import qualified Convert.Unique
 
-type Phase = AST -> AST
+type Phase = [AST] -> [AST]
 
 phases :: [Job.Exclude] -> [Phase]
 phases excludes =
@@ -49,9 +49,9 @@ phases excludes =
     , Convert.Typedef.convert
     , Convert.UnbasedUnsized.convert
     , Convert.Unique.convert
+    , Convert.NestPI.convert
     , selectExclude (Job.Interface, Convert.Interface.convert)
     , selectExclude (Job.Always   , Convert.AlwaysKW.convert)
-    , Convert.NestTF.convert
     ]
     where
         selectExclude :: (Job.Exclude, Phase) -> Phase
diff --git a/src/Convert/AlwaysKW.hs b/src/Convert/AlwaysKW.hs
index 1862234..1a57450 100644
--- a/src/Convert/AlwaysKW.hs
+++ b/src/Convert/AlwaysKW.hs
@@ -12,8 +12,8 @@ module Convert.AlwaysKW (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert = traverseDescriptions $ traverseModuleItems replaceAlwaysKW
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions $ traverseModuleItems replaceAlwaysKW
 
 replaceAlwaysKW :: ModuleItem -> ModuleItem
 replaceAlwaysKW (AlwaysC AlwaysComb stmt) =
diff --git a/src/Convert/AsgnOp.hs b/src/Convert/AsgnOp.hs
index b58feb5..8a808d0 100644
--- a/src/Convert/AsgnOp.hs
+++ b/src/Convert/AsgnOp.hs
@@ -11,9 +11,9 @@ module Convert.AsgnOp (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
+convert :: [AST] -> [AST]
 convert =
-    traverseDescriptions $ traverseModuleItems $
+    map $ traverseDescriptions $ traverseModuleItems $
     ( traverseStmts    convertStmt
     . traverseGenItems convertGenItem
     )
diff --git a/src/Convert/Assertion.hs b/src/Convert/Assertion.hs
index 870be76..3c811ad 100644
--- a/src/Convert/Assertion.hs
+++ b/src/Convert/Assertion.hs
@@ -9,8 +9,8 @@ module Convert.Assertion (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert = traverseDescriptions $ traverseModuleItems convertModuleItem
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions $ traverseModuleItems convertModuleItem
 
 convertModuleItem :: ModuleItem -> ModuleItem
 convertModuleItem (AssertionItem item) =
diff --git a/src/Convert/Bits.hs b/src/Convert/Bits.hs
index cab46af..1de13fc 100644
--- a/src/Convert/Bits.hs
+++ b/src/Convert/Bits.hs
@@ -24,8 +24,8 @@ import Language.SystemVerilog.AST
 
 type Info = Map.Map Identifier (Type, [Range])
 
-convert :: AST -> AST
-convert = traverseDescriptions convertDescription
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions convertDescription
 
 convertDescription :: Description -> Description
 convertDescription =
diff --git a/src/Convert/Enum.hs b/src/Convert/Enum.hs
index b0fb0d1..bfbac7e 100644
--- a/src/Convert/Enum.hs
+++ b/src/Convert/Enum.hs
@@ -33,8 +33,8 @@ type Enums = Set.Set EnumInfo
 type Idents = Set.Set Identifier
 type EnumItem = ((Range, Identifier), Expr)
 
-convert :: AST -> AST
-convert = traverseDescriptions convertDescription
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions convertDescription
 
 defaultType :: Type
 defaultType = IntegerVector TLogic Unspecified [(Number "31", Number "0")]
diff --git a/src/Convert/FuncRet.hs b/src/Convert/FuncRet.hs
index feb008c..79a64de 100644
--- a/src/Convert/FuncRet.hs
+++ b/src/Convert/FuncRet.hs
@@ -12,8 +12,8 @@ module Convert.FuncRet (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert = traverseDescriptions $ traverseModuleItems convertFunction
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions $ traverseModuleItems convertFunction
 
 convertFunction :: ModuleItem -> ModuleItem
 convertFunction (MIPackageItem (Function ml t f decls stmts)) =
diff --git a/src/Convert/Interface.hs b/src/Convert/Interface.hs
index 0d50a93..2c5c248 100644
--- a/src/Convert/Interface.hs
+++ b/src/Convert/Interface.hs
@@ -20,14 +20,15 @@ type Interfaces = Map.Map Identifier Interface
 type Modports = Map.Map Identifier [ModportDecl]
 type Modules = Map.Map (Identifier, Identifier) Type
 
-convert :: AST -> AST
+convert :: [AST] -> [AST]
 convert descriptions =
-    filter (not . isInterface) $
-    traverseDescriptions (convertDescription interfaces modules) $
-    descriptions
+    map (
+        filter (not . isInterface) .
+        traverseDescriptions (convertDescription interfaces modules)
+    ) descriptions
     where
         (interfaces, modules) =
-            execWriter $ collectDescriptionsM collectDesc descriptions
+            execWriter $ collectDescriptionsM collectDesc $ concat descriptions
         -- we can only collect/map non-extern interfaces
         collectDesc :: Description -> Writer (Interfaces, Modules) ()
         collectDesc (orig @ (Part False kw _ name ports items)) = do
diff --git a/src/Convert/KWArgs.hs b/src/Convert/KWArgs.hs
index 7db1725..38f4508 100644
--- a/src/Convert/KWArgs.hs
+++ b/src/Convert/KWArgs.hs
@@ -19,8 +19,8 @@ import Language.SystemVerilog.AST
 
 type TFs = Map.Map Identifier [Identifier]
 
-convert :: AST -> AST
-convert = traverseDescriptions convertDescription
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions convertDescription
 
 convertDescription :: Description -> Description
 convertDescription description =
diff --git a/src/Convert/Logic.hs b/src/Convert/Logic.hs
index 6ba89ed..a7f4bc6 100644
--- a/src/Convert/Logic.hs
+++ b/src/Convert/Logic.hs
@@ -33,11 +33,11 @@ import Language.SystemVerilog.AST
 type Idents = Set.Set Identifier
 type Ports = Map.Map (Identifier, Identifier) Direction
 
-convert :: AST -> AST
-convert ast =
-    traverseDescriptions (convertDescription ports) ast
+convert :: [AST] -> [AST]
+convert asts =
+    map (traverseDescriptions $ convertDescription ports) asts
     where
-        ports = execWriter $ collectDescriptionsM collectPortsM ast
+        ports = execWriter $ collectDescriptionsM collectPortsM $ concat asts
         collectPortsM :: Description -> Writer Ports ()
         collectPortsM (orig @ (Part _ _ _ name portNames _)) =
             collectModuleItemsM collectPortDirsM orig
diff --git a/src/Convert/NamedBlock.hs b/src/Convert/NamedBlock.hs
index b578ef8..ebcc473 100644
--- a/src/Convert/NamedBlock.hs
+++ b/src/Convert/NamedBlock.hs
@@ -18,12 +18,12 @@ import Language.SystemVerilog.AST
 
 type Idents = Set.Set Identifier
 
-convert :: AST -> AST
-convert ast =
+convert :: [AST] -> [AST]
+convert asts =
     -- we collect all the existing blocks in the first pass to make sure we
     -- don't generate conflicting names on repeated passes of this conversion
-    evalState (runner collectStmtM ast >>= runner traverseStmtM) Set.empty
-    where runner = traverseDescriptionsM . traverseModuleItemsM . traverseStmtsM
+    evalState (runner collectStmtM asts >>= runner traverseStmtM) Set.empty
+    where runner = mapM . traverseDescriptionsM . traverseModuleItemsM . traverseStmtsM
 
 collectStmtM :: Stmt -> State Idents Stmt
 collectStmtM (Block (Just x) decls stmts) = do
diff --git a/src/Convert/NestPI.hs b/src/Convert/NestPI.hs
new file mode 100644
index 0000000..0ec4da8
--- /dev/null
+++ b/src/Convert/NestPI.hs
@@ -0,0 +1,96 @@
+{- sv2v
+ - Author: Zachary Snow <zach@zachjs.com>
+ -
+ - Conversion for moving top-level package items into modules
+ -}
+
+module Convert.NestPI (convert) where
+
+import Control.Monad.State
+import Control.Monad.Writer
+import qualified Data.Map.Strict as Map
+import qualified Data.Set as Set
+
+import Convert.Traverse
+import Language.SystemVerilog.AST
+
+type PIs = Map.Map Identifier PackageItem
+type Idents = Set.Set Identifier
+
+convert :: [AST] -> [AST]
+convert asts =
+    map (filter (not . isPI) . nest) asts
+    where
+        nest :: AST -> AST
+        nest curr =
+            if next == curr
+                then curr
+                else nest next
+            where
+                next = evalState (traverseM curr) Map.empty
+                traverseM = traverseDescriptionsM traverseDescriptionM
+        isPI :: Description -> Bool
+        isPI (PackageItem item) = piName item /= Nothing
+        isPI _ = False
+
+-- collects and nests in tasks and functions missing from modules
+traverseDescriptionM :: Description -> State PIs Description
+traverseDescriptionM (PackageItem item) = do
+    () <- case piName item of
+        Nothing -> return ()
+        Just ident -> modify $ Map.insert ident item
+    return $ PackageItem item
+traverseDescriptionM (orig @ (Part extern kw lifetime name ports items)) = do
+    tfs <- get
+    let newItems = map MIPackageItem $ Map.elems $
+            Map.restrictKeys tfs neededPIs
+    return $ Part extern kw lifetime name ports (items ++ newItems)
+    where
+        existingPIs = execWriter $ collectModuleItemsM collectPIsM orig
+        runner f = execWriter $ collectModuleItemsM f orig
+        usedPIs = Set.unions $ map runner $
+            [ collectStmtsM collectSubroutinesM
+            , collectTypesM collectTypenamesM
+            , collectExprsM $ collectNestedExprsM collectIdentsM
+            ]
+        neededPIs = Set.difference usedPIs existingPIs
+traverseDescriptionM other = return other
+
+-- writes down the names of package items
+collectPIsM :: ModuleItem -> Writer Idents ()
+collectPIsM (MIPackageItem item) =
+    case piName item of
+        Nothing -> return ()
+        Just ident -> tell $ Set.singleton ident
+collectPIsM _ = return ()
+
+-- writes down the names of subroutine invocations
+collectSubroutinesM :: Stmt -> Writer Idents ()
+collectSubroutinesM (Subroutine f _) = tell $ Set.singleton f
+collectSubroutinesM _ = return ()
+
+-- writes down the names of function calls and identifiers
+collectIdentsM :: Expr -> Writer Idents ()
+collectIdentsM (Call    x _) = tell $ Set.singleton x
+collectIdentsM (Ident   x  ) = tell $ Set.singleton x
+collectIdentsM _ = return ()
+
+-- writes down aliased typenames
+collectTypenamesM :: Type -> Writer Idents ()
+collectTypenamesM (Alias x _) = tell $ Set.singleton x
+collectTypenamesM (Enum (Just t) _ _) = collectTypenamesM t
+collectTypenamesM (Struct _ fields _) = do
+    _ <- mapM collectTypenamesM $ map fst fields
+    return ()
+collectTypenamesM _ = return ()
+
+-- returns the "name" of a package item, if it has one
+piName :: PackageItem -> Maybe Identifier
+piName (Function _ _ ident _ _) = Just ident
+piName (Task     _   ident _ _) = Just ident
+piName (Typedef    _ ident    ) = Just ident
+piName (Decl (Variable _ _ ident _ _)) = Just ident
+piName (Decl (Parameter  _ ident   _)) = Just ident
+piName (Decl (Localparam _ ident   _)) = Just ident
+piName (Import _ _) = Nothing
+piName (Comment  _) = Nothing
diff --git a/src/Convert/NestTF.hs b/src/Convert/NestTF.hs
deleted file mode 100644
index 22b0dc7..0000000
--- a/src/Convert/NestTF.hs
+++ /dev/null
@@ -1,75 +0,0 @@
-{- sv2v
- - Author: Zachary Snow <zach@zachjs.com>
- -
- - Conversion for moving top-level tasks and functions into modules
- -}
-
-module Convert.NestTF (convert) where
-
-import Control.Monad.State
-import Control.Monad.Writer
-import qualified Data.Map.Strict as Map
-import qualified Data.Set as Set
-
-import Convert.Traverse
-import Language.SystemVerilog.AST
-
-type TFs = Map.Map Identifier PackageItem
-type Idents = Set.Set Identifier
-
-convert :: AST -> AST
-convert ast =
-    filter (not . isTF) $ nest $ ast
-    where
-        nest :: AST -> AST
-        nest curr =
-            if next == curr
-                then curr
-                else nest next
-            where
-                next = evalState (traverseM curr) Map.empty
-                traverseM = traverseDescriptionsM traverseDescriptionM
-        isTF :: Description -> Bool
-        isTF (PackageItem (Function _ _ _ _ _)) = True
-        isTF (PackageItem (Task     _   _ _ _)) = True
-        isTF _ = False
-
--- collects and nests in tasks and functions missing from modules
-traverseDescriptionM :: Description -> State TFs Description
-traverseDescriptionM (PackageItem item) = do
-    () <- case item of
-        Function _ _ ident _ _ -> modify $ Map.insert ident item
-        Task     _   ident _ _ -> modify $ Map.insert ident item
-        _ -> return ()
-    return $ PackageItem item
-traverseDescriptionM (orig @ (Part extern kw lifetime name ports items)) = do
-    tfs <- get
-    let newItems = map MIPackageItem $ Map.elems $
-            Map.restrictKeys tfs neededTFs
-    return $ Part extern kw lifetime name ports (items ++ newItems)
-    where
-        existingTFs = execWriter $ collectModuleItemsM collectTFsM orig
-        usedTFs = Set.union
-            (execWriter $ collectModuleItemsM (collectStmtsM collectSubroutinesM) orig)
-            (execWriter $ collectModuleItemsM (collectExprsM $ collectNestedExprsM collectCallsM) orig)
-        neededTFs = Set.difference usedTFs existingTFs
-traverseDescriptionM other = return other
-
--- writes down the names of tasks and functions
-collectTFsM :: ModuleItem -> Writer Idents ()
-collectTFsM (MIPackageItem item) =
-    case item of
-        Function _ _ ident _ _ -> tell $ Set.singleton ident
-        Task     _   ident _ _ -> tell $ Set.singleton ident
-        _ -> return ()
-collectTFsM _ = return ()
-
--- writes down the names of subroutine invocations
-collectSubroutinesM :: Stmt -> Writer Idents ()
-collectSubroutinesM (Subroutine f _) = tell $ Set.singleton f
-collectSubroutinesM _ = return ()
-
--- writes down the names of function calls
-collectCallsM :: Expr -> Writer Idents ()
-collectCallsM (Call f _) = tell $ Set.singleton f
-collectCallsM _ = return ()
diff --git a/src/Convert/PackedArray.hs b/src/Convert/PackedArray.hs
index 81ee1a4..d1c221b 100644
--- a/src/Convert/PackedArray.hs
+++ b/src/Convert/PackedArray.hs
@@ -31,8 +31,8 @@ data Info = Info
     { sTypeDims :: DimMap
     } deriving (Eq, Show)
 
-convert :: AST -> AST
-convert = traverseDescriptions convertDescription
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions convertDescription
 
 convertDescription :: Description -> Description
 convertDescription =
diff --git a/src/Convert/Return.hs b/src/Convert/Return.hs
index b51b3eb..26b9709 100644
--- a/src/Convert/Return.hs
+++ b/src/Convert/Return.hs
@@ -9,8 +9,8 @@ module Convert.Return (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert = traverseDescriptions $ traverseModuleItems convertFunction
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions $ traverseModuleItems convertFunction
 
 convertFunction :: ModuleItem -> ModuleItem
 convertFunction (MIPackageItem (Function ml t f decls stmts)) =
diff --git a/src/Convert/StarPort.hs b/src/Convert/StarPort.hs
index 3cce8bc..93c6532 100644
--- a/src/Convert/StarPort.hs
+++ b/src/Convert/StarPort.hs
@@ -12,11 +12,11 @@ import qualified Data.Map.Strict as Map
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert descriptions =
-    traverseDescriptions (traverseModuleItems mapInstance) descriptions
+convert :: [AST] -> [AST]
+convert asts =
+    map (traverseDescriptions $ traverseModuleItems mapInstance) asts
     where
-        modulePorts = execWriter $ collectDescriptionsM getPorts descriptions
+        modulePorts = execWriter $ collectDescriptionsM getPorts $ concat asts
         getPorts :: Description -> Writer (Map.Map Identifier [Identifier]) ()
         getPorts (Part _ _ _ name ports _) = tell $ Map.singleton name ports
         getPorts _ = return ()
diff --git a/src/Convert/StmtBlock.hs b/src/Convert/StmtBlock.hs
index 272f5ad..cbeeb73 100644
--- a/src/Convert/StmtBlock.hs
+++ b/src/Convert/StmtBlock.hs
@@ -10,8 +10,8 @@ module Convert.StmtBlock (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert = traverseDescriptions $ traverseModuleItems convertModuleItem
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions $ traverseModuleItems convertModuleItem
 
 convertModuleItem :: ModuleItem -> ModuleItem
 convertModuleItem (MIPackageItem packageItem) =
diff --git a/src/Convert/Struct.hs b/src/Convert/Struct.hs
index 73f3c05..6f40203 100644
--- a/src/Convert/Struct.hs
+++ b/src/Convert/Struct.hs
@@ -24,8 +24,8 @@ type Structs = Map.Map TypeFunc StructInfo
 type Types = Map.Map Identifier Type
 type Idents = Set.Set Identifier
 
-convert :: AST -> AST
-convert = traverseDescriptions convertDescription
+convert :: [AST] -> [AST]
+convert = map $ traverseDescriptions convertDescription
 
 convertDescription :: Description -> Description
 convertDescription (description @ (Part _ _ _ _ _ _)) =
diff --git a/src/Convert/Traverse.hs b/src/Convert/Traverse.hs
index 767edb5..329744f 100644
--- a/src/Convert/Traverse.hs
+++ b/src/Convert/Traverse.hs
@@ -562,8 +562,8 @@ traverseExprsM' strat exprMapper = moduleItemMapper
         return $ MIPackageItem $ Typedef t x
     moduleItemMapper (MIPackageItem (Comment c)) =
         return $ MIPackageItem $ Comment c
-    moduleItemMapper (MIPackageItem (Import imports)) =
-        return $ MIPackageItem $ Import imports
+    moduleItemMapper (MIPackageItem (Import x y)) =
+        return $ MIPackageItem $ Import x y
     moduleItemMapper (AssertionItem (mx, a)) = do
         a' <- traverseAssertionStmtsM stmtMapper a
         a'' <- traverseAssertionExprsM exprMapper a'
@@ -792,6 +792,8 @@ traverseTypesM mapper item =
             fullMapper t >>= \t' -> return $ Localparam t' x   e
         declMapper (Variable d t x a me) =
             fullMapper t >>= \t' -> return $ Variable d t' x a me
+        miMapper (MIPackageItem (Typedef t x)) =
+            fullMapper t >>= \t' -> return $ MIPackageItem $ Typedef t' x
         miMapper (MIPackageItem (Function l t x d s)) =
             fullMapper t >>= \t' -> return $ MIPackageItem $ Function l t' x d s
         miMapper (MIPackageItem (other @ (Task _ _ _ _))) =
diff --git a/src/Convert/Typedef.hs b/src/Convert/Typedef.hs
index b1da9ff..b58125d 100644
--- a/src/Convert/Typedef.hs
+++ b/src/Convert/Typedef.hs
@@ -17,8 +17,11 @@ import Language.SystemVerilog.AST
 
 type Types = Map.Map Identifier Type
 
-convert :: AST -> AST
-convert descriptions =
+convert :: [AST] -> [AST]
+convert = map convertFile
+
+convertFile :: AST -> AST
+convertFile descriptions =
     traverseDescriptions removeTypedef $
     traverseDescriptions (convertDescription types) $
     descriptions
diff --git a/src/Convert/UnbasedUnsized.hs b/src/Convert/UnbasedUnsized.hs
index 9f5746a..6734b82 100644
--- a/src/Convert/UnbasedUnsized.hs
+++ b/src/Convert/UnbasedUnsized.hs
@@ -13,8 +13,9 @@ module Convert.UnbasedUnsized (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
+convert :: [AST] -> [AST]
 convert =
+    map $
     traverseDescriptions $ traverseModuleItems $
     traverseExprs $ traverseNestedExprs convertExpr
 
diff --git a/src/Convert/Unique.hs b/src/Convert/Unique.hs
index b568537..e5793bf 100644
--- a/src/Convert/Unique.hs
+++ b/src/Convert/Unique.hs
@@ -13,8 +13,9 @@ module Convert.Unique (convert) where
 import Convert.Traverse
 import Language.SystemVerilog.AST
 
-convert :: AST -> AST
-convert = traverseDescriptions $ traverseModuleItems $ traverseStmts convertStmt
+convert :: [AST] -> [AST]
+convert =
+    map $ traverseDescriptions $ traverseModuleItems $ traverseStmts convertStmt
 
 convertStmt :: Stmt -> Stmt
 convertStmt (If (Just _) cc s1 s2) =
diff --git a/src/Language/SystemVerilog/AST/Description.hs b/src/Language/SystemVerilog/AST/Description.hs
index fd3f8d4..357890d 100644
--- a/src/Language/SystemVerilog/AST/Description.hs
+++ b/src/Language/SystemVerilog/AST/Description.hs
@@ -56,7 +56,7 @@ data PackageItem
     = Typedef Type Identifier
     | Function (Maybe Lifetime) Type Identifier [Decl] [Stmt]
     | Task     (Maybe Lifetime)      Identifier [Decl] [Stmt]
-    | Import [(Identifier, Maybe Identifier)]
+    | Import Identifier (Maybe Identifier)
     | Decl Decl
     | Comment String
     deriving Eq
@@ -71,11 +71,7 @@ instance Show PackageItem where
         printf "task %s%s;\n%s\n%s\nendtask"
             (showLifetime ml) x (indent $ show i)
             (indent $ unlines' $ map show b)
-    show (Import imports) =
-        printf "import %s;"
-            (commas $ map showImport imports)
-        where
-            showImport (x, y) = printf "%s::%s" x (fromMaybe "*" y)
+    show (Import x y) = printf "import %s::%s;" x (fromMaybe "*" y)
     show (Decl decl) = show decl
     show (Comment c) =
         if elem '\n' c
diff --git a/src/Language/SystemVerilog/Parser/Parse.y b/src/Language/SystemVerilog/Parser/Parse.y
index 44eb0fb..acce7d0 100644
--- a/src/Language/SystemVerilog/Parser/Parse.y
+++ b/src/Language/SystemVerilog/Parser/Parse.y
@@ -454,7 +454,7 @@ NonGenerateModuleItem :: { [ModuleItem] }
   | "initial" Stmt                       { [Initial $2] }
   | "genvar" Identifiers ";"             { map Genvar $2 }
   | "modport" ModportItems ";"           { map (uncurry Modport) $2 }
-  | NonDeclPackageItem                   { [MIPackageItem $1] }
+  | NonDeclPackageItem                   { map MIPackageItem $1 }
   | NInputGateKW  NInputGates  ";"       { map (\(a, b, c) -> NInputGate  $1 a b c) $2 }
   | NOutputGateKW NOutputGates ";"       { map (\(a, b, c) -> NOutputGate $1 a b c) $2 }
   | AttributeInstance ModuleItem         { map (MIAttr $1) $2 }
@@ -570,12 +570,12 @@ PackageItems :: { [PackageItem] }
 PackageItem :: { [PackageItem] }
   : DeclTokens(";")                     { map Decl $ parseDTsAsDecls $1 }
   | ParameterDecl(ParameterDeclKW, ";") { map Decl $1 }
-  | NonDeclPackageItem                  { [$1] }
-NonDeclPackageItem :: { PackageItem }
-  : "typedef" Type Identifier ";" { Typedef $2 $3 }
-  | "function" opt(Lifetime) FuncRetAndName TFItems DeclsAndStmts "endfunction" opt(Tag) { Function $2 (fst $3) (snd $3) (map defaultFuncInput $ (map makeInput $4) ++ fst $5) (snd $5) }
-  | "task" opt(Lifetime) Identifier TFItems DeclsAndStmts "endtask" opt(Tag) { Task $2 $3 (map defaultFuncInput $ $4 ++ fst $5) (snd $5) }
-  | "import" PackageImportItems ";" { Import $2 }
+  | NonDeclPackageItem                  { $1 }
+NonDeclPackageItem :: { [PackageItem] }
+  : "typedef" Type Identifier ";" { [Typedef $2 $3] }
+  | "function" opt(Lifetime) FuncRetAndName TFItems DeclsAndStmts "endfunction" opt(Tag) { [Function $2 (fst $3) (snd $3) (map defaultFuncInput $ (map makeInput $4) ++ fst $5) (snd $5)] }
+  | "task" opt(Lifetime) Identifier TFItems DeclsAndStmts "endtask" opt(Tag) { [Task $2 $3 (map defaultFuncInput $ $4 ++ fst $5) (snd $5)] }
+  | "import" PackageImportItems ";" { map (uncurry Import) $2 }
 
 PackageImportItems :: { [(Identifier, Maybe Identifier)] }
   : PackageImportItem                        { [$1] }
diff --git a/src/sv2v.hs b/src/sv2v.hs
index a1fd27e..97e2995 100644
--- a/src/sv2v.hs
+++ b/src/sv2v.hs
@@ -25,9 +25,8 @@ main = do
     let includePaths = incdir job
     let defines = map splitDefine $ define job
     asts <- mapM (parseFile includePaths defines) (files job)
-    let ast = concat asts
     -- convert the file
-    let ast' = convert (exclude job) ast
+    let asts' = convert (exclude job) asts
     -- print the converted file out
-    hPrint stdout ast'
+    hPrint stdout $ concat asts'
     exitSuccess
diff --git a/sv2v.cabal b/sv2v.cabal
index 640453b..504e56a 100644
--- a/sv2v.cabal
+++ b/sv2v.cabal
@@ -63,7 +63,7 @@ executable sv2v
     Convert.KWArgs
     Convert.Logic
     Convert.NamedBlock
-    Convert.NestTF
+    Convert.NestPI
     Convert.PackedArray
     Convert.Return
     Convert.StarPort
diff --git a/test/basic/top_tf.sv b/test/basic/top_tf.sv
index aacf101..82ac717 100644
--- a/test/basic/top_tf.sv
+++ b/test/basic/top_tf.sv
@@ -9,7 +9,9 @@ function baz;
     input [2:0] n;
     baz = n * 2;
 endfunction
+localparam PARAM = 37;
 module top;
     initial foo();
     initial $display("bar(0) = %d", bar(0));
+    initial $display("PARAM = %d", PARAM);
 endmodule
diff --git a/test/basic/top_tf.v b/test/basic/top_tf.v
index e78679a..c36d2b5 100644
--- a/test/basic/top_tf.v
+++ b/test/basic/top_tf.v
@@ -10,6 +10,8 @@ module top;
         input [2:0] n;
         baz = n * 2;
     endfunction
+    localparam PARAM = 37;
     initial foo();
     initial $display("bar(0) = %d", bar(0));
+    initial $display("PARAM = %d", PARAM);
 endmodule