--- /dev/null
+# Extends the class object with class and instance accessors for class attributes,
+# just like the native attr* accessors for instance attributes.
+#
+# class Person
+# cattr_accessor :hair_colors
+# end
+#
+# Person.hair_colors = [:brown, :black, :blonde, :red]
+class Class
+ def cattr_reader(*syms)
+ syms.flatten.each do |sym|
+ next if sym.is_a?(Hash)
+ class_eval(<<-EOS, __FILE__, __LINE__)
+ unless defined? @@#{sym}
+ @@#{sym} = nil
+ end
+
+ def self.#{sym}
+ @@#{sym}
+ end
+
+ def #{sym}
+ @@#{sym}
+ end
+ EOS
+ end
+ end
+
+ def cattr_writer(*syms)
+ options = syms.extract_options!
+ syms.flatten.each do |sym|
+ class_eval(<<-EOS, __FILE__, __LINE__)
+ unless defined? @@#{sym}
+ @@#{sym} = nil
+ end
+
+ def self.#{sym}=(obj)
+ @@#{sym} = obj
+ end
+
+ #{"
+ def #{sym}=(obj)
+ @@#{sym} = obj
+ end
+ " unless options[:instance_writer] == false }
+ EOS
+ end
+ end
+
+ def cattr_accessor(*syms)
+ cattr_reader(*syms)
+ cattr_writer(*syms)
+ end
+end