instiki/vendor/rails/activesupport/lib/active_support/core_ext/class/delegating_attributes.rb
Jacques Distler 4e14ccc74d Instiki 0.16.3: Rails 2.3.0
Instiki now runs on the Rails 2.3.0 Candidate Release.
Among other improvements, this means that it now 
automagically selects between WEBrick and Mongrel.

Just run

    ./instiki --daemon
2009-02-04 14:26:08 -06:00

48 lines
2.4 KiB
Ruby

# These class attributes behave something like the class
# inheritable accessors. But instead of copying the hash over at
# the time the subclass is first defined, the accessors simply
# delegate to their superclass unless they have been given a
# specific value. This stops the strange situation where values
# set after class definition don't get applied to subclasses.
class Class
def superclass_delegating_reader(*names)
class_name_to_stop_searching_on = self.superclass.name.blank? ? "Object" : self.superclass.name
names.each do |name|
class_eval <<-EOS
def self.#{name} # def self.only_reader
if defined?(@#{name}) # if defined?(@only_reader)
@#{name} # @only_reader
elsif superclass < #{class_name_to_stop_searching_on} && # elsif superclass < Object &&
superclass.respond_to?(:#{name}) # superclass.respond_to?(:only_reader)
superclass.#{name} # superclass.only_reader
end # end
end # end
def #{name} # def only_reader
self.class.#{name} # self.class.only_reader
end # end
def self.#{name}? # def self.only_reader?
!!#{name} # !!only_reader
end # end
def #{name}? # def only_reader?
!!#{name} # !!only_reader
end # end
EOS
end
end
def superclass_delegating_writer(*names)
names.each do |name|
class_eval <<-EOS
def self.#{name}=(value) # def self.only_writer=(value)
@#{name} = value # @only_writer = value
end # end
EOS
end
end
def superclass_delegating_accessor(*names)
superclass_delegating_reader(*names)
superclass_delegating_writer(*names)
end
end