[EMAIL PROTECTED] wrote: > Aahz> Taking a look at __slots__ is fine as long as you don't actually > Aahz> use them. > > Gabriel> Why? > > Skip> > http://groups.google.com/group/comp.lang.python/browse_thread/thread/451ad25f9c648404/f4ac2dfde32b16fd?lnk=st&q=Python+__slots__+aahz&rnum=2#f4ac2dfde32b16fd > > Patrick> The subject of __slots__ really seems to get some people's > Patrick> dander up, to the extent where the heat/light ratio in the > Patrick> discussion becomes uncomfortably high. Right here, we have > Patrick> Skip referring to a post by Aahz, where Aahz says that Guido > Patrick> says that slots are bad mojo, without anybody ever giving > Patrick> concrete examples about why this may be the case. The only > Patrick> assertion that was made explicitly enough to be testable came > Patrick> about in a followup to Aahz's original post, only AFTER someone > Patrick> asked what the side-effects associated with __slots__ were. > Patrick> Aahz responded: > > No dander on my part. I was just pointing out an earlier thread on the > topic. Note however that the ultimate source of the anti-slots fervor in > that thread is Guido himself (may he live long and prosper as BDFL). If > Guido thinks it's bad mojo, that's good enough for me. Also, if he thinks > it's bad mojo now, my suspicion is that you won't see it in Py3k. > > That said, It's not mentioned on the Python3.0 page of the wiki: > > http://wiki.python.org/moin/Python3.0 > > or in PEP 3000: > > http://www.python.org/dev/peps/pep-3000/ > > and I see no discussion about it in the Python 3000 mailing list archives: > > http://mail.python.org/pipermail/python-3000/ > > though Ian Bicking asks about it here: > > > http://wiki.python.org/moin/Python3%2e0Suggestions#head-fc89a0fe3f697418776925f4828ea863031fbbd2 > > Skip
I didn't actually sense any dander on your part, so it was probably a bit unfortunate that I chose to respond to that particular message. I do (rightly or wrongly) sense some dander on Aahz's part, and this was the second or third thread where I saw him respond in a similar terse fashion, but I wasn't really motivated to respond until I saw your response to his response to, well, you know... And I know that the BDFL thinks it's a mistake, and he's probably right. In my previous post, I attempted to rationalize why this is true. For a start, Guido is probably continually hounded by people asking stupid __slots__ questions. Nonetheless, this is one of the few topics on CLP where innocent, rational questions are more often than not answered with "because I said so", so I was trying to inject a bit of nuance into the discussion. (For most similar technical questions, someone will post a pointer to a post or document which explains in clear technical detail WHY things are bad, but for this issue there seems to be no comparable source -- just that rant of the BDFL, which certainly carries a lot of weight in terms of best practices, but which I find woefully inadequate in terms of explanations which are dumbed-down enough for me to follow.) Also, as I noted, I _do_ use them on occasion, so if there really _are_ potential pitfalls there, I would like to understand exactly what they are, so my ears perk up whenever I notice a __slots__ discussion, but so far I have been repeatedly disappointed, in that I always see someone saying "don't do that" but I have never seen a cogent technical argument about how my scripts which __slots__ are going to suddenly, irretrievably break one day. Regards, Pat -- http://mail.python.org/mailman/listinfo/python-list
