diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index a024c1c..690c7bb 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -108,13 +108,14 @@ Style/BlockDelimiters:
     - 'spec/comma/data_extractor_spec.rb'
     - 'spec/comma/header_extractor_spec.rb'
 
-# Offense count: 11
+# Offense count: 12
 # Configuration parameters: AllowedConstants.
 Style/Documentation:
   Exclude:
     - 'spec/**/*'
     - 'test/**/*'
     - 'lib/comma/array.rb'
+    - 'lib/comma/collection_export.rb'
     - 'lib/comma/data_extractor.rb'
     - 'lib/comma/data_mapper_collection.rb'
     - 'lib/comma/extractor.rb'
diff --git a/lib/comma.rb b/lib/comma.rb
index 1350d1c..3a1dd78 100644
--- a/lib/comma.rb
+++ b/lib/comma.rb
@@ -11,10 +11,10 @@ module Comma
   }.freeze
 end
 
-require 'comma/data_mapper_collection' if defined? DataMapper
-
 require 'comma/options'
 require 'comma/generator'
+require 'comma/collection_export'
+require 'comma/data_mapper_collection' if defined? DataMapper
 require 'comma/array'
 require 'comma/object'
 
diff --git a/lib/comma/array.rb b/lib/comma/array.rb
index f1b1c50..f15906f 100644
--- a/lib/comma/array.rb
+++ b/lib/comma/array.rb
@@ -1,7 +1,5 @@
 # frozen_string_literal: true
 
 class Array
-  def to_comma(style = :default)
-    Comma::Generator.new(self, style).run(:each)
-  end
+  include Comma::CollectionExport
 end
diff --git a/lib/comma/collection_export.rb b/lib/comma/collection_export.rb
new file mode 100644
index 0000000..2f88b43
--- /dev/null
+++ b/lib/comma/collection_export.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Comma
+  module CollectionExport
+    def to_comma(style = :default)
+      Comma::Generator.new(self, style).run(:each)
+    end
+  end
+end
diff --git a/lib/comma/data_mapper_collection.rb b/lib/comma/data_mapper_collection.rb
index 9f61335..d05c6cc 100644
--- a/lib/comma/data_mapper_collection.rb
+++ b/lib/comma/data_mapper_collection.rb
@@ -3,9 +3,7 @@
 if defined?(DataMapper)
   module DataMapper
     class Collection
-      def to_comma(style = :default)
-        Comma::Generator.new(self, style).run(:each)
-      end
+      include Comma::CollectionExport
     end
   end
 end
diff --git a/lib/comma/mongoid.rb b/lib/comma/mongoid.rb
index 33d7399..fed1254 100644
--- a/lib/comma/mongoid.rb
+++ b/lib/comma/mongoid.rb
@@ -6,9 +6,7 @@
 
   module Mongoid
     class Criteria
-      def to_comma(style = :default)
-        Comma::Generator.new(self, style).run(:each)
-      end
+      include Comma::CollectionExport
     end
   end
 rescue LoadError => e