From: Tom Sawyer <transami@...>
Date: 2003-01-07T15:00:26+09:00
Subject: Re: attr_cast, one a small step for interface techniques

here you go, in full! (by the way the old attr_accessor does not depend on 
attr_reader or attr_writer. go figure. this new one does.) let me know if you 
see any problems with this.

  alias attr_reader_basic attr_reader

  def attr_reader(*args)
    if args.last.kind_of?(Hash) or args.last.kind_of?(Array)
      attr_reader_with_cast *(args.pop)
    end
    attr_reader_basic *args
  end

  def attr_reader_with_cast(*args)
    args.each { |name, cast|
      class_eval <<-EOS
        def #{name}()
          @#{name}.#{cast}
        end
      EOS
    }
  end

  alias attr_writer_basic attr_writer

  def attr_writer(*args)
    if args.last.kind_of?(Hash) or args.last.kind_of?(Array)
      attr_writer_with_cast *(args.pop)
    end
    attr_writer_basic *args
  end

  def attr_writer_with_cast(*args)
    args.each { |name, cast|
      class_eval <<-EOS
        def #{name}=(arg)
          @#{name} = arg.#{cast}
        end
      EOS
    }
  end

  alias attr_accessor_basic attr_accessor

  def attr_accessor(*args)
    attr_reader *args
    attr_writer *args
  end

  def attr_accessor_with_cast(*args)
    attr_writer_with_cast *args
    attr_reader_with_cast *args
  end


-transami