From: Phrogz <gavin@...>
Date: 2007-05-10T07:40:05+09:00
Subject: Re: using dynamic method calling with attr_writer methods

On May 9, 2:10 pm, Markus Hohenhaus <mark...@hni.upb.de> wrote:
> That's it!! Thanks. Now everything works as expected. Allthough I like
> mine better, seems more
> logical to me ;).

Well, you can do that too, if you like:

class Module
  def attr_readwrite( *methods )
    class_eval{
      methods.each{ |method_name|
        define_method( method_name ){ |*val|
          val = val.first
          unless val.nil?
            instance_variable_set( "@#{method_name}", val )
          else
            instance_variable_get( "@#{method_name}" )
          end
        }
      }
    }
  end
end

class Foo
  attr_readwrite :foo, :bar
end

f = Foo.new

f.foo( 42 )
p f.foo
#=> 42
f.foo( 12 )
p f.foo
#=> 12


(I think there's a more elegant way to define the method and detect if
it received a value, but I was too lazy to figure it out.)

I'm pretty sure Ara T. Howard's 'attributes' gem also gives you the
ability to do what you want, where calling the method without a
parameter acts as a getter, and calling it with a parameter acts as a
setter. And I bet his way is clean. :)