Posted by metacello on Feb 21, 2011; 2:47pm
URL: https://forum.world.st/Issue-110-in-metacello-Running-a-visitor-over-configuration-tp3317455.html

Status: Accepted
Owner: [hidden email]
Labels: Type-Feature Priority-Medium

New issue 110 by [hidden email]: Running a visitor over configuration
http://code.google.com/p/metacello/issues/detail?id=110

What we exchanged on the mailing list:


On 02/18/2011 08:10 AM, Alexandre Bergel wrote:
Hi!

Is there a way to run a visitor over a graph of dependent configuration?
If no, would it be difficult to have?

Cheers,
Alexandre

There is no way to run a generic visitor over the graph of dependent  
configurations.

The directives structure is a visitable representation of the configuration  
load graph, but it doesn't have what you are looking for (I think), because  
the directive builder doesn't follow paths for projects whose version is <=  
the scheduled project version.

To put a generic visitor in place, you could piggyback/generalize the  
directives structure builder (fetch pass).

Keep in mind that in traversing the dependent configuration structure there  
are a large number of redundant paths (one of the contributing factors to  
long load times in past versions), so quite a bit of bookkeeping is  
necessary to avoid traversing the same path over and over again ... Having  
been this route multiple times already I would lean towards adding the  
necessary information to the directive structure.

Dale