lib/lightgbm/booster.rb in lightgbm-0.3.3 vs lib/lightgbm/booster.rb in lightgbm-0.3.4

@@ -49,10 +49,10 @@
       out_str.read_string
     end
     alias_method :to_json, :dump_model
 
     def eval_valid
-      @name_valid_sets.each_with_index.map { |n, i| inner_eval(n, i + 1) }.flatten(1)
+      @name_valid_sets.each_with_index.flat_map { |n, i| inner_eval(n, i + 1) }
     end
 
     def eval_train
       inner_eval(train_data_name, 0)
     end