Re: empty classes as c structs?

[Steven Bethard]

Alex Martelli wrote:
Steven Bethard <[EMAIL PROTECTED]> wrote:
I don't know what the right solution is here...  I wonder if I should
write a classmethod-style descriptor that disallows the calling of a 
function from an instance?  Or maybe I should just document that the 
classmethods should only be called from the class?  Hmm...

Another approach is to add a few "reserved words" to the ones Python
itself would reject in the initialization.  Just you cannot do:
    b = Bunch(continue=23)
you may choose to forbid using getDict=42 - if you do that you probably
want to forbid any magicname too, since e.g.
    b = Bunch(__dict__=99)
can't work ``right'' no matter what, while setting e.g. __deepcopy__
similarly might confuse any copy.deepcopy(b), etc, etc.
Yeah, I thought about this.  I certainly don't have any problem with 
disallowing magic names.  For other names, I'm less certain...

How do you feel about getDict and setDict also being classmethods?
Uh?  I want to get or set the dict of a specific instance -- not those
of the whole class.  How would you design them as classmethods...?
The classmethod would have to be called with an instance, e.g.:
class Bunch(object):
    @classmethod
    def getDict(cls, self):
        return self.__dict__
    @classmethod
    def setDict(cls, self, dct):
        self.__dict__ = dct
Of course, these could be staticmethods instead since they don't need 
the class, but the point is that you should be calling them like:

    adict = Bunch.getDict(bunch)
or
    Bunch.setDict(bunch, adict)
The complications with attribute hiding is one of main reasons I've 
tried to minimize the number of methods associated with Bunch...

Steve
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