Rails - Apr 2005 - Mixing the Model & DB definitions (again)

I had a possibly new spin on this same issue. How about specially
encoding the model<-->DB definitions into specially formatted comments
in the ActiveRecord model? The purpose here is:
* give me one place to figure out the definition of a given model (the
relationships, the methods, and the data members as well)
* let me stay away from raw SQL, if possible
* stay DRY

So, how about:

---
model Article < ActiveRecord::Base

  #:= title varchar(64)
  #:= description varchar(255)
  #:= rating int(5)

  has_many :authors

  def some_method
    ...
  end

end
---

Above, "#:=" is treated as comment, but it can also be parsed out as a
meta-definition for SQL usage. Once I define my models, I could run a
script like:

./script/model2db Article

which would look at the model definition, parse for the DB
definitions, and inject that into the schema (possibly altering the
table if it already exists). It seems DRY enough. What do you all
think?

     -d

> which would look at the model definition, parse for the DB
> definitions, and inject that into the schema (possibly altering the
> table if it already exists). It seems DRY enough. What do you all
> think?
Look in the archive for discussions on Migrations. I describe the way 
these definitions will eventually find their way into AR. But as real 
code, not comments.
--
David Heinemeier Hansson,
http://www.basecamphq.com/   -- Web-based Project Management
http://www.rubyonrails.org/  -- Web-application framework for Ruby
http://www.loudthinking.com/ -- Broadcasting Brain