1 files changed, 58 insertions, 0 deletions
diff --git a/actionpack/lib/action_view/template/types.rb b/actionpack/lib/action_view/template/types.rb
new file mode 100644
index 0000000000..7611c9e708
--- /dev/null
+++ b/actionpack/lib/action_view/template/types.rb
@@ -0,0 +1,58 @@
+require 'set'
+require 'active_support/core_ext/class/attribute_accessors'
+require 'active_support/core_ext/object/blank'
+
+module ActionView
+  class Template
+    class Types
+      class Type
+        cattr_accessor :types
+        self.types = Set.new
+
+        def self.register(*t)
+          types.merge(t.map { |type| type.to_s })
+        end
+
+        register :html, :text, :js, :css,  :xml, :json
+
+        def self.[](type)
+          return type if type.is_a?(self)
+
+          if type.is_a?(Symbol) || types.member?(type.to_s)
+            new(type)
+          end
+        end
+
+        attr_reader :symbol
+
+        def initialize(symbol)
+          @symbol = symbol.to_sym
+        end
+
+        delegate :to_s, :to_sym, :to => :symbol
+        alias to_str to_s
+
+        def ref
+          to_sym || to_s
+        end
+
+        def ==(type)
+          return false if type.blank?
+          symbol.to_sym == type.to_sym
+        end
+      end
+
+      cattr_accessor :type_klass
+
+      def self.delegate_to(klass)
+        self.type_klass = klass
+      end
+
+      delegate_to Type
+
+      def self.[](type)
+        type_klass[type]
+      end
+    end
+  end
+end