[Zope3-dev] Packaging conventions (was Re: PyCon DC 2003: Call For Papers)

[Jim Fulton]

Phillip J. Eby wrote:
> At 04:28 PM 12/13/02 -0500, Jim Fulton wrote:
> 
>> Phillip J. Eby wrote:
>> ..
>>
>>> from peak.naming import api as naming
>>
>>
>> And this is good ... why?
> 
> 
> 1. Everything in the naming API is then only one dot away
> 
> 2. Access is via a prefix ("naming.") so the top-level namespace in the 
> importing module isn't cluttered or conflicting.

You don't need an api module for this. You could just:

   from peak import naming

...

>> What is the advantage of api over __init__?
> 
> 
> Makes it possible for packages which want to reuse part of a package, 
> not to require the whole thing to be imported.  This can slash the 
> startup and runtimes for small scripts enormously (in proportion to the 
> script's total run time).

But then these can't import api either, as api would have the same
effect.

I would say that __init__ should only expose things that are really
always wanted. A package could have other modules, useful in some cases
that aren't exposed by init.

> There are also some advantages to simplifying import order for 
> interdependent packages; For example, if you have a package A whose 
> classes want to provide an interface from package B, but package B 
> contains things that depend on A's classes.  Being able to say:
> 
> A:
> from B.interfaces import ISomething
> 
> B:
> from B.somemodule import Something
> 
> Without having to sort out a precise ordering in the package __init__ 
> modules can be a nice convenience.

I'm confused. Neither of the above import api.  I also don't
follow the second example.

Jim


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