[Zope3-dev] Container interface issues

[Jim Fulton]

Martijn Faassen wrote:
> Jim Fulton wrote:
> 
>>- It's simpler for clients, as they can use a familiar syntax.
>>
>>Given the fact that containers must always be manipulated through
>>adapters, clients can't use the __setitem__ and __delitem__ operations
>>directly, so the second benefit goes away. In fact, the presense
>>of __setitem__ and __delitem__ might tempt clients to use them,
>>making them a liability.

...

I'm not sure what you are quoting here, but it's out of date.

As it turned out, clients do use __setitem__ and __delitem__. No adapters
are necessary. Containers are responsiblke for publishing events and
for maintaining __parent__ and __name__.  This is made pretty trivial
through two helper functions.

> I think __setitem__ and __delitem__ are a liability them. Since
> __getitem__ is defined it is very natural to try to use __setitem__
> and it will seem to work, but it'll be buggy. I don't think adding
> clear documentation shouting loudly somewhere is a good way to solve
> that problem.
> 
> Therefore I think it shouldn't be called __setitem__ and __delitem__, unless
> of course these can be made to do the right thing after all.

They do do the right thing after all.  If you are quoting a current proposal,
please let me know which one so I can fix it.

Jim


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