[Zope-dev] Re: ZPatterns.... more thoughts about implimentation of a concrete system... system...

[Steve Alexander]

Steve Spicklemire wrote:
> 
> Every couple of weeks I get a little time to work on this stuff...
> well, it's been a couple weeks. ;-)

Keep them coming :-)

> the generic dataskins could simply acquire the methods that
> they need from the specialist....

> This all begs some questions....
> 
> (1) Is this 'reasonable'? Is anyone else using methods of specialists
>     this way?

Let's think of an example from real life.

Let's say we have a Person class. We also have a Prison specialist.

When a Person is in Prison, they are given a Prisoner propertysheet with
properties like state_prisoner_id, security_category, admission_date,
sentence_length.

A person also has different capabilities when in prison. In general,
people can do different things depending on where they are; behaviour
depends on type and on context.

In prison, a many of the things a person can normally do are forbidden;
for example, acquire and spend money. There are also additional things a
person can do: see their probation officer; book a family visit.

I think your suggestion of having methods in a specialist that get
acquired by classes managed by that specialist generally fits in with
the thought-experiment of persons in prison. However, perhaps a Folder
w/ Customizer Support, and methods in that folder that are made
available via acquisition, is a better match still.


> (2) is it worth enforcing the use by acquisition? e.g.,

I'm not sure what the benefit would be. Perhaps there could be a plug-in
tab in a specialist for "methods acquired by rackmounted dataskins".

> (3) Has anyone found a better way to adorn 'plain' objects with methods?

I've used ordinary acquisition, as described just above.

You can use Transparent folders to keep things organized neatly.

--
Steve Alexander
Software Engineer
Cat-Box limited
http://www.cat-box.net