base/immutable_queue.rb in maroon-0.7.1 vs base/immutable_queue.rb in maroon-0.8.0

@@ -25,10 +25,10 @@
       [head, ImmutableQueue.new(f, b)]
     end
   end
 
   def self.empty
-    @@empty ||= ImmutableQueue.new(ImmutableStack::empty, ImmutableStack::empty)
+    @empty ||= ImmutableQueue.new(ImmutableStack::empty, ImmutableStack::empty)
   end
 
   def push_array(arr)
     q = self
     if arr
\ No newline at end of file