[Zope-dev] [Checkins] SVN: zope.intid/trunk/ - Remove a dependency on ``zope.container.contained.Contained``

[Martijn Faassen]

Stephan Richter wrote:
> On Friday 15 May 2009, Fred Drake wrote:
>> Keeping the dependency graph clean is great, and there's plenty to do
>> there. But there's also something to be said about being able to keep
>> a substantial portion of it in your head.  The cleanliness of the
>> graph isn't so important if most users still can't understand just
>> because there are so many pieces that they wouldn't normally use
>> directly.
> 
> Yes, I have voiced that concern several times myself. I personally do not even 
> understand where all this fear of installing many packages comes from. I 
> think it is because the ZCML is pulling in too many default registrations and 
> people are afraid of those, which I understand. But to create new packages 
> just because you do not want to use other parts of it is silly.

That's not silly at all.

I'm not afraid of installing many packages for my applications. But for 
libraries and little frameworks, I don't like having to depend on 70 
other packages even though my library isn't using 99.9% of the code in 
there in any way. Is that silly?

We created zope.container because we don't want to use all the code in 
zope.app.container. zope.app.container contains the ZMI a lot of code we 
don't want to be there in our apps as we're not intending to use it. Is 
that silly?

The zope.browser package was created to prevent, among other things, 
z3c.form from pulling in code from zope.formlib, a completely separate 
form library. But it wasn't a good situation. People actually got 
confused and thought they had something to do with each other, in that 
z3c.form uses zope.formlib, which it doesn't. Is preventing that 
situation silly?

The principle has to do more with *less code* than *less packages*. 
We're trying to make it possible to use and be aware of less code when 
considering individual chunks of the code base. To create loose coupling 
so that you don't have to worry about all chunks of the codebase even 
though you're only concerned with a little bit of it. To get rid of the 
code that isn't used a lot (such as the ZMI).

If we can make our zope.* packages not rely on a huge amount of other 
packages that they aren't really using anyway, we stand a larger change 
understanding them ourselves, and we stand a larger change others might 
understand them too and adopt them.

I could understand these concerns with package creation better if people 
would point out how the total amount of packages installed for an 
application or library is increasing (once the applications and 
libraries have been adjusted to import from the new locations). But I 
think the amount of packages is decreasing...

Regards,

Martijn