[support] how blocks work and "garbage collection"?

[Ivan Sergio Borgonovo]

Hi,

I've a long list of categories (external to drupal taxonomy) and for
each category I'd like to provide a block that offer some category
aggregate info.

I'd like to keep the block list/configure interface
(admin/build/block), so that users could decide if, where and when
those aggregate info should be displayed.
But I can't present the whole list of categories in the block
interface.

As an example I picked up views to see how to dynamically create
blocks.

But it doesn't seem that views do any garbage collection in the
{blocks} table after a view is deleted.

A better example was core menu module that actually does some
clean up.

Even themes leaves a lot of garbage in {blocks}.

How this is supposed to work?

Do you have a general approach to suggest to this problem?
Does a module already exist to do some clean up?
eg. a couple of switches that will ask:
- would you like to clean all blocks assigned to a not installed
  module?
- would you like to clean all blocks that are assigned to a not
  installed theme?

Shouldn't a policy exist in the docs to ask modules/themes to do
their own clean-up?

I saw this problem seems to be solved in D7.

-- 
Ivan Sergio Borgonovo
http://www.webthatworks.it