traversal.rb in grumlin-0.14.3

- old
+ new

@@ -3,10 +3,10 @@
 module Grumlin
   class Traversal
     # TODO: add other start steps
     SUPPORTED_STEPS = %i[E V addE addV].freeze
 
-    CONFIGURATION_STEPS = %i[withSideEffect].freeze
+    CONFIGURATION_STEPS = %i[withSack withSideEffect].freeze
 
     attr_reader :configuration_steps
 
     def initialize(pool = Grumlin.default_pool, configuration_steps: [])
       @pool = pool