tdiff.rb in tdiff-0.4.0

- old
+ new

@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 #
 # {TDiff} adds the ability to calculate the differences between two tree-like
 # objects. Simply include {TDiff} into the class which represents the tree
 # nodes and define the {#tdiff_each_child} and {#tdiff_equal} methods.
 #