From: Peter Vanbroekhoven <calamitates@...>
Date: 2005-10-20T00:30:11+09:00
Subject: Re: [RCR] Cut-based AOP

On Wed, 19 Oct 2005, Jeff Wood wrote:

> Although I see the power of the examples and the ideas, it seems like
> it's a bit watered down compared to AspectJ or other Aspect
> frameworks.
>
> Usually, the definition of cuts allow you to wrap many things at once...
>
> AspectJ ( for instance ) allows you to use wildcards in both the
> object type and the  method names that are getting wrapped.  It allows
> you to add general functionality ( like debugging logs or security
> control ) very easily to chunks ( of any size, even all ) of your
> application.
>
> I'd like to see something like that for Ruby, but I do think that your
> idea is a good start.
>
> maybe something that allows cut to take some wildcards
>
> Cut.new( "FileLogging" ) do
>
>  wrap_method( File, :any ) do |method, *args|
>    # do logging stuff
>    method.call( *args )
>    # do more logging stuff
>  end
>
> end
>
> or instead of File ...simply
>
>  wrap_method( IO, :any ) ...
>    ...
>  end
>
> which would turn around and add this cut to any object of that type (
> or a derivative ) of IO
>
> Anyways, just additional thoughts.  Shouldn't be too hard to implement
> as objects now within Ruby as it exists...
>
> The only trick is catching overrides and new types that are defined
> AFTER the cut has been added.
>
> ... just my $0.02US

Thanks for contribution ;-)

Well, I think we are aware of this. Cuts provide the basis of AOP, namely 
the basic wrapping functionality, and providing a convenient handle to the 
wrapping methods. These things can then be used in a full-fledged AOP 
library that provides wildcards and all. But I think the important point 
is that we think that cuts are a good basis for AOP. Anything on top of 
that is sugar. And because cuts fit well within Ruby's OO system, it will 
be good sugar!

Peter