Namespace HashWithIndifferentAccess

activesupport/lib/active_support/core_ext/hash/indifferent_access.rb

@@ -2,7 +2,7 @@
 
 class Hash
   def with_indifferent_access
-    hash = HashWithIndifferentAccess.new(self)
+    hash = ActiveSupport::HashWithIndifferentAccess.new(self)
     hash.default = self.default
     hash
   end

activesupport/lib/active_support/hash_with_indifferent_access.rb

@@ -2,7 +2,8 @@
 # people can write params[:key] instead of params['key']
 # and they get the same value for both keys.
 
-class HashWithIndifferentAccess < Hash
+module ActiveSupport
+  class HashWithIndifferentAccess < Hash
     def initialize(constructor = {})
       if constructor.is_a?(Hash)
         super()
@@ -126,4 +127,7 @@ def convert_value(value)
           value
         end
       end
+  end
 end
+
+HashWithIndifferentAccess = ActiveSupport::HashWithIndifferentAccess