[Zope3-dev] Re: adapter registration question

[Jean-Marc Orliaguet]

Philipp von Weitershausen wrote:
> Dieter Maurer wrote:
>> Philipp von Weitershausen wrote at 2006-11-15 15:08 +0100:
>>> ...
>>>> def myStrAdapter(something):
>>>>    return str(something)
>>> It instantiates a 'str' object. The 'str' object is the adapter for 
>>> 'something'.
>>
>> Huh? This would be a severe terminology abuse:
>
> I agree, it's bending the terminology a lot. It wasn't me who came up 
> with the 'str' and 'int' example.
>
>>   An adapter should adapt something to something else *BUT*
>>   an "str" object does not adapt anything (it does not operate on
>>   another object).
>
> Well, imagine
>
>   >>> str(123)
>   '123'
>
> Here '123' is the 'str' adapter of the integer 123. It's conceptually 
> the same if you do
>
>   >>> IZopeDublinCore(myobj)
>
> except that in the str(123) case, you call the class directly instead 
> of using the Component Architecture's registry as a flexible dispatch.
>

But I guess Chris wanted to keep the registry lookup part, but not to 
have to adapt the context.

in other words a utility that converts something to a string based on 
the type to be converted.

once you have that utility / adapter you should be able to call it like:

   converter = getAdapterFor(123, type=IToStringConverter)
   strResult = converter.convert(123)

and reuse it:

   strResult2 = converter.convert(456)

that saves a lot of CPU / memory.

PS: calling '123' an adapter is really bending concepts.

/JM