Streamline this code a bit, no functional changes

src/Control/Abstract/Value.hs

@@ -29,6 +29,9 @@ class (MonadEvaluator t v m) => MonadValue t v m where
   -- | Construct an abstract string value.
   string :: ByteString -> m v
 
+  -- | Construct an abstract interface value.
+  interface :: v -> m v
+
   -- | Eliminate boolean values. TODO: s/boolean/truthy
   ifthenelse :: v -> m v -> m v -> m v
 
@@ -40,8 +43,6 @@ class (MonadEvaluator t v m) => MonadValue t v m where
   -- | Extract the environment from an interface value.
   environment :: v -> m (EnvironmentFor v)
 
-  interface :: v -> m v
-
 -- | Construct a 'Value' wrapping the value arguments (if any).
 instance ( FreeVariables t
          , MonadAddressable location (Value location t) m

src/Data/Syntax/Declaration.hs

@@ -232,20 +232,16 @@ instance Evaluatable Import2 where
     env <- getGlobalEnv
     putGlobalEnv mempty
     importedEnv <- require name
-    env' <- Map.foldrWithKey (\k v rest -> do
+    env' <- Map.foldrWithKey copy (pure env) (unEnvironment importedEnv)
-      if Map.null symbols
-         -- Copy over all symbols in the environment under their qualified names.
-        then envInsert (prefix <> k) v <$> rest
-        -- Only copy over specified symbols, possibly aliasing them.
-        else maybe rest (\symAlias -> envInsert symAlias v <$> rest) (Map.lookup k symbols)
-      ) (pure env) (unEnvironment importedEnv)
-
     modifyGlobalEnv (const env')
     unit
     where
       name = qualifiedName (subterm from)
-      symbols = Map.fromList xs
       prefix = qualifiedName (subterm alias) <> "."
+      symbols = Map.fromList xs
+      copy = if Map.null symbols then qualifyInsert else directInsert
+      qualifyInsert k v rest = envInsert (prefix <> k) v <$> rest
+      directInsert k v rest = maybe rest (\symAlias -> envInsert symAlias v <$> rest) (Map.lookup k symbols)
 
 
 -- | A wildcard import