2 files changed, 12 insertions, 0 deletions
diff --git a/lib/psych/deprecated.rb b/lib/psych/deprecated.rb
index b306b85..1d401d9 100644
--- a/lib/psych/deprecated.rb
+++ b/lib/psych/deprecated.rb
@@ -50,6 +50,12 @@ module Psych
     key = [domain, type_tag].join ':'
     @domain_types[key] = [key, block]
   end
+
+  def self.tagurize thing
+    warn "#{caller[0]}: add_private_type is deprecated, use add_domain_type" if $VERBOSE
+    return thing unless String === thing
+    "tag:yaml.org,2002:#{thing}"
+  end
 end
 
 class Object
diff --git a/test/psych/test_deprecated.rb b/test/psych/test_deprecated.rb
index c2c8a97..6db7238 100644
--- a/test/psych/test_deprecated.rb
+++ b/test/psych/test_deprecated.rb
@@ -181,5 +181,11 @@ module Psych
 
       assert_equal [["x-private:foo", "bar"]], types
     end
+
+    def test_tagurize
+      assert_nil Psych.tagurize nil
+      assert_equal Psych, Psych.tagurize(Psych)
+      assert_equal 'tag:yaml.org,2002:foo', Psych.tagurize('foo')
+    end
   end
 end