diff --git a/lib/compass/sass_extensions/functions/lists.rb b/lib/compass/sass_extensions/functions/lists.rb
index e82a6757..a9e15a0c 100644
--- a/lib/compass/sass_extensions/functions/lists.rb
+++ b/lib/compass/sass_extensions/functions/lists.rb
@@ -18,8 +18,9 @@ module Compass::SassExtensions::Functions::Lists
   def compact(*args)
     sep = :comma
     if args.size == 1 && args.first.is_a?(Sass::Script::List)
-      args = args.first.value
-      sep = args.first.separator
+      list = args.first
+      args = list.value
+      sep = list.separator
     end
     Sass::Script::List.new(args.reject{|a| !a.to_bool}, sep)
   end