From: Joel VanderWerf <vjoel@...>
Date: 2005-07-23T09:14:34+09:00
Subject: Re: Class Attributes and rdoc/Observable

Hadmut Danisch wrote:
> Hi,
> 
> two questions or proposals about class attributes:

Do you really mean "class attributes", or "class methods which define
attributes of instances" ? From your questions, it sounds like the latter.

> - If the access methods for a class variable are defined with
>   attr_accessor, rdoc shows them as [RW] in the attributes list.
> 
>   But when the access method is explicitely defined with def,
>   then rdoc does not show it as attribute access, but as an
>   instance function.
> 
>   Sometimes it would be nice to explicitely write the
>   attr= or attr methods (e.g. to do some checks or give default
>   values), but to have it listed in the documentation as a
>   plain attribute.
> 
>   Is there a way to make rdoc recognize methods as attribute
>   methods?
> 
>   If not, I'd propose a #:attr:  flag.

There was some discussion of that recently:

http://blade.nagaokaut.ac.jp/cgi-bin/vframe.rb/ruby/ruby-talk/147750?147700-148826

> - Is it possible to make attr_writer and attr_accessor notify
>   Observers if the value changes? If not, I'd propose to
>   define versions that do so.

There's my implementation of that idea at:

http://raa.ruby-lang.org/project/observable/

>   If I do understand ruby correctly, then this would mean to
>   add new functions like oattr_writer to the Module class.

My version defines an Observable module that you can extend your class with.