Ticket #122: modeldiscuss_cleanedup.txt

File modeldiscuss_cleanedup.txt, 34.0 KB (added by rmunn@…, 12 years ago)

IRC discussion with tabs cleaned up so it's easier to read

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1           * Now talking on #django
2           * Topic for #django is: http://www.djangoproject.com/ || Django is a high-level Python Web framework that encourages rapid development and clean, pragmatic design.|| Logs: http://loglibrary.com/show_page/latest/179
3           * Topic for #django set by JZ_ at Sat Jul 16 12:30:01 2005
4       hugo- hi
5   mmarshall hi hugo-
6           * adrian_h is back.
7    adrian_h back
8   mmarshall Ok everyone, we can start talking again ;)
9       rmunn adrian_h: You said you're split on #122. What are your main objections?
10           * ljoramo has quit ()
11           * adrian_h gathers thoughts
12       rmunn Take your time. :-)
13    adrian_h I don't like the fact that ForeignKeys are name-less attributes of the class (yes, I was the one who suggested that behavior in the first place)
14       rmunn That would be a little surprising for newbies, yeah.
15    adrian_h Before we open-sourced Django, the field name was required. Foreign keys used to look like this:
16    adrian_h meta.IntegerField('field_name', 'verbose name', rel=meta.ManyToOne(Poll))
17    adrian_h So I shortened that to "ForeignKey(Poll)" in preparation for open-sourcing
18           * Netminder likes the current state of fields FWIW.
19    adrian_h But the one thing that was lost in that was that now you have to "guess" what the field names are, for use in meta.admin.fields
20    adrian_h I talked about this with MikeLambert last night
21       rmunn I personally would have little objection to making ForeignKeys require a name again...
22       hugo- me too
23       rmunn It's orthogonal to the question of the SQLObject-like syntax, IMHO.
24       rmunn Actually, requiring ForeignKeys (and ManyToManyFields) to have a name would get rid of one of the more "magic" parts of the #122 patch.
25    adrian_h As I see it, the issues are related, because one solution can solve both problems
26    adrian_h Yeah, exactly
27       rmunn They're related, but independent: it would be quite feasible to implement one, or the other, or both, or neither.
28       rmunn One of those four is probably optimum, we just need to figure out which.
29       rmunn Another possibility: in mmarshall's email to the dev list, he mentioned writing a wrapper class for the new behavior.
30       rmunn I would suggest making the new behavior the default, but keeping a wrapper class ("meta.OldModel" perhaps) around to give the old "fields tuple" behavior.
31    adrian_h Yeah, that's possible...But there should be One Real Way of doing it
32    adrian_h Yes, we've discussed meta.OldModel (with exactly that name)
33       rmunn The documentation would mention the "fieldname = CharField()" syntax only, and the BackwardsIncompatibilities page would say "As a transition measure, use meta.OldModel until you've converted all your models".
34   mmarshall rmunn: That was what I tried to do at first, but there were some problems.
35       rmunn mmarshall: What problems did you run into?
36    adrian_h IIRC, the problem lies in the fact that django/models/__init__.py can't be duplicated
37    adrian_h i.e., we can't have multiple copies of it
38   mmarshall For one thing, the changes were not local meta.Model; they also required switching the first two arguments to the Field classes.
39       rmunn Ah yes, so that verbose_name could become the first positional arg.
40   mmarshall So I tried duplicating meta itself, resulting in a new can of worms.
41   mmarshall rmunn: Yes.
42   mmarshall At first, I had a hack to get around this, but it was messy, and prone to confuse people.
43       rmunn So if this is going to happen, it sounds like the simplest way is to just bite the bullet and say, "OK folks, revision ### is going to break all your models. Here's how to convert to the new syntax."
44    adrian_h Yeah...And, realistically, having to change models to use the "fieldname = class" syntax is only slightly more work than changing models to use "meta.OldModel"
45       rmunn How would you feel about the "fieldname = class" syntax if the decision was made that ForeignKeys must always be given a name?
46   mmarshall Yeah, it's really not that big of a deal.  Although, after converting all of the models in the tests and the django internals, as well as my own, I got a little sick of it.
47           * threeve has quit ()
48       rmunn Any other major objections?
49       rmunn That was to adrian_h, of course, not mmarshall. :-)
50       rmunn mmarshall: But it's a one-time price.
51    adrian_h My only other major objection is having to ask everybody to change model syntax
52    adrian_h Which isn't a huge problem, being that we haven't guaranteed backwards-compatibility
53       rmunn Well, there's no getting around that one.
54       rmunn It'll mostly depend on whether people want the new syntax or not.
55    adrian_h And yesterday's session update was backwards-incompatible, and people didn't complain too loudly...
56   Netminder adrian_h: very few people had gotten to sessions yet
57       rmunn If there are loud boos and very few cheers, you could always revert the patch...
58   mmarshall Yeah, but that wasn't as big of deal to change.
59       rmunn I, for one, would be cheering loudly. :-)
60   Netminder changing the model syntax is pretty big.
61    adrian_h Netminder: Yes, but the session change broke admin installations, because the admin now depends on sessions
62       rmunn Yeah, it is, which is why I'm trying to start discussion on the dev list.
63    adrian_h People haven't really spoken up about the model syntax, other than rmunn and mmarshall
64   mmarshall I have had a number of people mention it to me.
65       rmunn manuzhai was saying earlier in here that he planned to write a post to the dev list.
66           * Tybstar (n=tgerla@cpe-069-134-162-085.nc.res.rr.com) has joined #django
67   Netminder adrian_h: I'd probably be mildly against it, as I don't feel a "big gain" in the new syntax vs. the current and it'd be a good bit of work and relearnin'
68    adrian_h How does manuzhai feel about it?
69       rmunn loglibrary's not working, so I'll just copy and paste:
70       rmunn manuzhai: "will send a me too to the #122 thread once I get an email from it"
71    adrian_h Netminder: all right
72           * Tybstar returns
73    adrian_h Tybstar: How do you feel about the proposed model syntax change to use "fieldname = FieldClass"?
74   mmarshall When I came in earlier, he mentioned that #122 was 'shot down', and frowned.
75       rmunn manuzhai: "I for one like 'your' syntax better" (to mmarshall)
76   Netminder adrian_h: I heard some rumbles on the ticket about issues with the db layer.  Is that a show stopper or just something to get around?
77           * liquidx (n=liquidx@87.240.134.143) has joined #django
78       hugo- I don't think that it really is much change in the syntax. Actually that's the reason why I am a bit split on #122, too - I don't see much gain for the work
79     Tybstar adrian_h: i haven't really followed the discussion, unfortunately. i liked it on first glance, but i've really gotten attached to the current syntax.
80   Netminder yes, that's my thought too hugo-
81       hugo- ok, sure, the new syntax would be nicer, but is it really that big a problem to use a list of fields instead of a list of attribute assignments?
82     Tybstar it's not a huge difference either way...
83       rmunn It's not a huge gain once you've gotten used to the fields = (...) syntax. I see it more as a big gain for newbies.
84       hugo- is  it really?
85   Netminder It's just... different.
86    adrian_h Netminder: There shouldn't be any issues with the DB layer with regard to the possible syntax change -- the syntax is abstracted
87   Netminder adrian_h: roger that.
88       hugo- if I think about what questions arise here in the channel, I don't think that _that_ part of Django really produces that much questions
89       rmunn Ah good, some real discussion at last. :-)
90    adrian_h Great point, hugo-
91       hugo- there are other things like the settings file an dstuff like that :-)
92     Tybstar the model fields syntax isn't bad. the admin = syntax can be pretty hairy.
93     Tybstar i've seen lots of people have trouble wtih the (foo) != (foo,) thing in the admin = code
94       rmunn I've seen that too.
95       hugo- Tybstar: yeah, that's one thing I allways want to hit Guido over the head because of ;-)
96   Netminder the (foo,) syntax becomes second nature after a messup or two
97       rmunn I'd suggest a general rule-of-thumb: if something is supposed to be a list or tuple, and you get a string, automatically convert it.
98    adrian_h The one real problem I have with the model syntax is that it's not immediately apparent what the field name is for a ForeignKey and ManyToManyField, so people don't know what to use in admin.fields
99     Tybstar adrian_h: indeed
100     Tybstar takes some guesswork
101       hugo- Tybstar: especially since python will happily iterate over chars in a string if it expects a list :-)
102     Tybstar yes
103    adrian_h We can fix that with the model validator, with a message that says "That's an invalid field name. Here are the valid field names for this model", but that's still one step too much
104     Tybstar the pitfalls of a dynamically typed langage. :)
105       hugo- adrian_h: I would applaud a move that ForeignKey and friends need a obligatory first parameter that is the field name like other field types
106       rmunn That's what ticket #244 was about.
107       hugo- adrian_h: especially since that would make writing models for existing databases much more obvious
108       hugo- adrian_h: especially since the "name=" option for ForeignKey isn't (or at least wasn't) documented in the model reference :-)
109       rmunn Wow, discussion moved on while I was searching for that ticket.
110       rmunn I meant that http://code.djangoproject.com/ticket/244 was about being nicer to newbies.
111       hugo- rmunn: you need to configure --with-threads ;-)
112       rmunn Heh. I wish IRC had that sometimes... :-)
113    adrian_h :)
114    adrian_h hugo-: Would you applaud the move if it were in "fieldname = FieldClass" syntax?
115   Netminder irc --with-productivity would be nice
116   mmarshall Netminder: LOL
117       rmunn Netminder: :-D
118       rmunn Okay, let me see who seems to like or dislike the "fieldname = FieldClass" syntax.
119       rmunn I like it.
120       rmunn mmarhsall likes it.
121       rmunn adrian_h is split but leaning against (?)
122       rmunn Netminder isn't too enthusiastic.
123       hugo- adrian_h: I wouldn't mind if it was, as I don't have much models to change - but I still wouldn't see the reason to switch that part of the syntax. But I wouldn't actively object.
124       rmunn Tybstar liked it at first but is pretty indifferent.
125       rmunn hugo- doesn't much care.
126   mmarshall garthk likes it, manuzhai likes it
127       hugo- rmunn: doesn't much care with added a bit of puzzlement, please ;-)
128       rmunn Anyone object to how I've described them?
129    adrian_h I'm positively *for* requiring a name for ForeignKey and ManyToManyField, to make that explicit -- which is a related issue
130       hugo- adrian_h: that one I am quite positive about, too
131       rmunn adrian_h: I'm +1 on requiring a name as well.
132   Netminder rmunn: that's about right.  +1 on the requirement
133   mmarshall +1 on requiring a name here
134     Tybstar +1
135    adrian_h Wow, no opposition to the name requirement -- very cool
136     rfc1149 count me in :) +1 on requiring a name
137     Tybstar sounds unaniniminninnious
138   mmarshall I normally specify a name anyway :P
139    adrian_h rfc1149: What do you think of the "fieldname=FieldClass" syntax?
140    adrian_h As an aside, can anybody on Windows confirm this bug? http://code.djangoproject.com/ticket/349
141     rfc1149 i quite like the fieldname=FieldClass idea, but am a bit concerned that it will bite later.  using fields= leaves a lot of namespace for later use.
142    adrian_h rfc1149: The idea is that other (non-field) data would go in an inner class called "Meta"
143     rfc1149 btw, i also would like to interpret "foo" as ("foo",) in settings where it makes sense
144     rfc1149 oh, that would be very nice!
145     rfc1149 (the inner Meta class, that is)
146       rmunn What I see is support for fieldname=FieldClass ranging from mild to enthusiastic, but I don't see any opposition stronger than mild.
147       rmunn Is there anyone who would positively scream if that was implemented?
148       rmunn Remember, it would be a backwards-incompatible change to the model syntax, so it would involve work (albeit a one-time effort) on your part to change your models.
149     rfc1149 i do not yet have significant amounts of existing code, but i would not like it if an unthinking svn update would break all my code
150           * Netminder remains mildly against it.
151     rfc1149 but i guess that is unavoidable :)
152    adrian_h Here's an example of the new syntax, so people have something to look at: http://django.pastebin.com/339441
153   Netminder I'd kinda grumble a bit while rewriting my todo app :)
154     rfc1149 and it's still not yet released :)
155           * Boffbowsh (i=Boffbows@host-85-236-105-19.multiplaydsl.co.uk) has joined #django
156     rfc1149 the field=FieldClass syntax really looks clean and natural
157       rmunn Boffbowsh: Have you looked at http://code.djangoproject.com/ticket/122 at all?
158     rfc1149 and friendly to newbies.. i'm liking it more and more.
159       hugo- I'd prefer it if the inner class wasn't tacked on by magic but instead just be added via a __meta__ = something attribute
160   Netminder yeah, it's kinda nice.  My only objection would be the one time fee that we'd have to pay, but I think it would be worth it in the long run.
161   Boffbowsh yeah, i've taken a look, if thats'the fieldname = fielddef thing
162   Boffbowsh i agree it would be nice
163       rmunn I'm trying to get a feel for whether people would really like that syntax, really hate it, or be indifferent.
164   Netminder yeah, I'm not keen on the magic
165       hugo- field names with __ in front and back could be defined as "internal use" - that would match with python thinking
166   Boffbowsh but not at the expense of ease of maintenance of django, imo
167   Netminder +1 on hugo's line of thought
168   Boffbowsh yar
169     rfc1149 Boffbowsh:  that's a good point
170       rmunn hugo-: Interesting idea.
171     rfc1149 but i have not really heard adrian_h complain about it
172    adrian_h If we use fieldname=fielddef, the maintenance will be about the same as it is now
173       rmunn Perhaps __meta__ = dict(admin=Admin(), foo=Bar(), ...)
174     rfc1149 see :)
175   Boffbowsh i don't mind having a slightly odd syntax (which isn't really that odd at all, there's just a slightly nicer way) if it means that the rest of the project is stable and easy to add new stuff to
176    adrian_h But the last patch to #122 (which allows model attributes without names) would be a headache to maintain
177   Boffbowsh not read it through thoruoghly as i was at work when it first cropped up
178     rfc1149 i personally prefer Meta: ... above __meta__ = dict( ... )
179    adrian_h Using a class for Meta would be better, because you wouldn't have to use commas between attributes
180   Netminder hmm yeah
181    adrian_h Models themselves used to be dictionaries, a long time ago
182   Boffbowsh are there any benefits other than it looking nicer?
183       hugo- adrian_h: yeah, but the problem is with the way how you find out in your Poll class that there is an inner class Meta
184   mmarshall adrian_h: how would it be hard to maintain?
185       rmunn There seems to be pretty much unanimous consensus to require a name for ForeignKey and ManyToManyFields, so the headache-to-maintain patch can probably go away.
186   Netminder if it looks prettier but is painful to maintain, that's no good
187       hugo- there is no obvious connection between those two besides the scope - the internally needed assignments are done by magic
188    adrian_h mmarshall: I was referring to the magic no-name-for-ForeignKeys thing, but we've agreed to scrap that.
189           * rfc1149 goes to bed but looks forward to reading the rest of the discussion later
190           * Dagur (n=dagur@dsl-196-5.hive.is) has joined #django
191       rmunn rfc1149: Don't log out -- loglibrary is down.
192       hugo- and more specificially: there is no prior art in Python libraries for such magic that connects stuff implicitely just because of the scope they are in
193    adrian_h hugo-: You're talking about the internal "class Meta", right?
194       hugo- adrian_h: yep
195       hugo- I agree that it's cleaner syntax, though. <sigh> not an easy choice
196       hugo- the hacker in me would go the inner-class-way, the maintainer might shy away from it :-)
197   Netminder I'm still on the fence, but think maintainability is a key thing to think about
198   Netminder the syntax is quite nice though :)
199    adrian_h The maintenance for the inner class is simple -- internally (inside the metaclass call), it's just interpreted as another attribute on the object
200       rmunn I'm looking at things more from a usability perspective than a maintainability perspective, so that colors my perception.
201       rmunn Most of the tickets I file tend to be useability issues, if you've noticed.
202    adrian_h It's even probably a bit cleaner than the current internals
203    adrian_h rmunn: Yes, and they're much appreciated :)
204       Dagur Could someone tell me what this error means:
205       Dagur ContentTypeDoesNotExist: ContentType does not exist for {'package__label__exact': 'jenga', 'python_module_name__exact': 'jengacats'}
206       Dagur I get it when I try to submit stuff in the admin panel
207       rmunn Dagur: Have you changed your model recently?
208       Dagur yeah
209       hugo- adrian_h: the nice thing about the current stuff is: it's all python data. The new stuff is more python code objects. It's easy to programmatically generate python data if there is much repetitive stuff in it - but it's much harder (although not impossible thanks to pythons structure) to dynamically construct code objets
210    adrian_h Dagur: run "django-admin.py sqlall jenga" and execute the "INSERT INTO content_types ... jenga" line in your database.
211       rmunn Did you update the database after changing the model?
212       Dagur it's a model I created for an existing database
213       Dagur I didn't try that
214       Dagur will do
215       rmunn Dagur: Then you'll need to run sqlall, like adrian_h said.
216       rmunn But you'll also need to add all the auth_* and core_* tables.
217       hugo- adrian_h: and since I am in a line of business where there are often very large repetitive strikes of code and field definitions, I am much in favor of easy generating things programmatically
218       rmunn So that the INSERT INTO statements have somewhere to put the data. :-)
219    adrian_h Dagur: After doing "django-admin.py init", just do "django-admin.py sqlinitialdata jenga"
220       hugo- adrian_h: so in that aspect the maintainer in me shys away from solutions that leave the data-path and go the code path, even though the hacker in me prefers to hack on the latter stuff
221       hugo- usually the maintainer in me kicks the butt of the hacker in me ...
222       Dagur ok i'm confused now
223       rmunn hugo-: I *think*, though I'm not sure, that mmarshall's patch contructs a "fields" tuple internally.
224       rmunn Dagur: Listen to adran_h, not me. He knows what he's talking about.
225       Dagur hehe ok
226           * rheinbot has quit (Remote closed the connection)
227           * Tybstar needs a viewsvn for his project
228    adrian_h Dagur: Run the command "django-admin.py init" if you haven't already done that. That creates Django's internal database tables.
229   Netminder Tybstar: see the one that slashzero put django_ajax on, it's free to all
230           * Tybstar ponders writing a django-based viewsvn
231    adrian_h Dagur: After you've done that, run "django-admin.py sqlinitialdata jenga" and execute that SQL in your database.
232    adrian_h Dagur: That's it.
233       hugo- Tybstar: use trac
234           * rheinbot (n=supybot@maxwell.servers.ljworld.com) has joined #django
235       rmunn hugo-: Trac's internal Subversion viewer annoys me a little.
236     Tybstar hugo-: looks kinda heavyweight
237       rmunn It doesn't let me see what the root of the repository is.
238       rmunn I have to guess what to put after "svn checkout".
239       hugo- Tybstar: it isn't - I use it for most of my repositories nowadays, it's easy to set up and run
240       hugo- rmunn: hey, there is a wiki in it, just add a description of the checkout path to the wiki :-)
241           * Notify: jacobkm is offline (kornbluth.freenode.net).
242       Dagur woo! it worked
243       Dagur thanks
244    adrian_h Dagur: No problem! Thanks for using Django
245   Netminder Dagur: drive through :)
246       Dagur ^_^
247           * Tybstar can't make viewsvn work
248       Dagur I have another error for you guys :P
249    adrian_h Dagur: Go ahead
250       Dagur TypeError: got unexpected keyword argument 'id__iexactjengausers'
251       rmunn hugo-: Not every project that uses Trac seems to do that, though. That's my main gripe. It's a pretty small one, as gripes go.
252       Dagur the problem is that the id fields are called ID (capitalized)
253    adrian_h Dagur: Where did that error happen?
254       Dagur i was submitting in the admin panel
255           * GvaderTH (i=grzegorz@mokotow.com) has left #django
256    adrian_h Dagur: Can you paste the full traceback to django.pastebin.com?
257       Dagur http://django.pastebin.com/339455
258    adrian_h Thanks...I'm looking now
259       Dagur it's the id of a foreignkey table
260       Dagur not the table I'm updating
261           * wilsonian has quit ()
262       Dagur oops
263       Dagur id__iexactjengausers   <-- the jengausers part is something I added
264       Dagur it's supposed to say id__iexact
265    adrian_h OK, I was wondering about that :)
266       Dagur sorry, I was trying to figure out the table name
267    adrian_h No problem
268   mmarshall hugo-: My patch simply itenerates over all of the attributes.  If the attribute holds an instance of Field, it assigns the name (or rel_name, for relationship fields) from the attribute name, and adds it to a 'fields' list.  This list is then used just the same as the fields tuple is currently.
269    adrian_h mmarshall: Ideally it would just loop over all the attributes except the one (if given) named "Meta"
270       rmunn Dagur: Is that "iexact" a typo that's supposed to be "exact", or did you really mean "iexact"?
271   mmarshall adrian_h: Actually, that's what it does.
272           * GvaderTH (n=gregtech@mokotow.com) has joined #django
273    adrian_h mmarshall: Ah, cool
274    adrian_h rmunn: That iexact is within Django...I'm fixing now.
275       hugo- adrian_h: and so I can't name a field Meta? yuck.
276   mmarshall Also, if it comes accross an attribute that is neither a Field nor a function, it raises a helpful error.
277       Dagur rmunn: it's the django code that does that
278       Dagur I was just submitting a form
279   mmarshall hugo-: Originally I supported doing that, by optionally placing all fields in a subclass named 'Fields', but Adrian didn't like that.
280    adrian_h Dagur: "svn update" your code, and let me know whether the problem is fixed.
281       Dagur ok
282       hugo- hmm. the more I think it through, the more I would tend to -1 on the new field syntax
283   mmarshall hugo-: actually, you can still do that, just by giving the 'name' argument.
284       Dagur worked!
285    adrian_h Dagur: Thanks for pointing out that bug!
286    adrian_h Dagur: Sorry, I should've credited you in the commit message
287       Dagur np, my pleasure!
288    adrian_h hugo-: One solution to that might be to require that "class Meta" is a subclass of "meta.Meta" or something like that
289    adrian_h "class Meta(meta.Meta)" -- hehe
290       rmunn Ew, that's a little overboard.
291       rmunn What about "class __meta__: ..."
292    adrian_h Is that possible?
293       hugo- sure
294       rmunn I don't see why not, it's just another name in the namespace.
295    adrian_h Very cool -- I just tried it
296       rmunn Let me check and make sure.
297           * hugo- has a class named __proxy__ in one of his source files :-)
298       rmunn Oh, nevermind then.
299    adrian_h Now that's much better, namespace-wise
300       rmunn Anyone who's using double-underscores at the start and end of their field names is being unpythonic, IMHO.
301    adrian_h But it introduces more double underscores :-/
302     Tybstar i'd suggest against __meta__
303       rmunn Yeah, that's the downside.
304     Tybstar it implies python builtin magic
305       hugo- rmunn: ugh - python uses loads of __xxxx__ stuff - is it unpythonic? :-)
306     Tybstar _Meta would be better
307   Netminder eew
308       rmunn hugo-: Fields are public things, __xxxx__ is for private stuff.
309   Netminder I'd take __meta__ before _Meta
310       hugo- and there are special provisions in python with regard to __xxxxx fields - they are hidden in some aspects
311    adrian_h hugo-: That's actually an advantage in this case
312       hugo- rmunn: the meta stuff _is_ private to the model, not public :-)
313    adrian_h What about "class DjangoMeta"?
314       hugo- but the reason why I dislike the new stuff is that it doesn't allow me to do things like fields = tuple([IntegerField(name, default=0) for name in list_of_fieldnames]) or something similar as easily
315    adrian_h That's much less likely to be used as a field name
316     Tybstar Netminder: i don't necessarily like _Meta better than __meta__, but i'm afraid of collidiing with python internals someday
317       rmunn What I meant was that "class __meta__" won't interfere with anyone's DB field name, since you should be using double-underscores for DB fields (which are more "public" attributes).
318    adrian_h hugo-: Interesting point, but, realistically, why would you want to do that, other than laziness? Models don't change often enough for there to be a need for them to be dynamic like that.
319       hugo- sure, if I know about the inner workings I can hack around it - but I can't just take the public visible interface of the model and apply python code there
320       hugo- adrian_h: laziness is my second name ;-)
321    adrian_h hehe
322       hugo- adrian_h: and for a more serious reason: I am working in legacy apps areas where you get _large_ structures of many very similar fields
323       hugo- if you have to write models with 100 or more fields and most of them are booleans or moneytypes or some choice of a handfull of possibilities, you crave for automatted solutions
324     Tybstar my cat just caught a blue jay.
325    adrian_h hugo-: "print ','.join(["IntegerField(%s, default=0)" % name for name in list_of_fieldnames])"
326       hugo- adrian_h: nooo - I hate generated code, programmatic solutions should just manipulate data
327       hugo- so to do the same with the new stuff I would write a loop that does a load of setattr(...)
328       hugo- it's not impossible, it's just not as easy and simple as with data structures
329    adrian_h hugo-: setattr wouldn't even work, because the metaclass runs when the class is *defined*
330       hugo- ah, yes, forgotten that one
331    adrian_h I must say, the new syntax is sexy
332       rmunn I suppose you could construct a dict and feed it to meta.Model.__new__(cls, bases, attrs). Ew.
333       rmunn I don't even know if that would work.
334       hugo- rmunn: yep, with metaclasses that would be a - rather ugly, I must say - option
335    adrian_h Or dynamically construct a class and dynamically set its parent class after it's been constructed?
336       hugo- sure, you can allways call the metaclass manually and construct the class instance by using the metaclass. It's a bit hacky and doesn't sound like really maintainable code, though ;-)
337       rmunn adrian_h: The metaclass magic happens before the class object is created, so I don't think that would work.
338           * manuzhai (n=manuzhai@i249181.upc-i.chello.nl) has joined #django
339       rmunn hugo-: You'd have to really deeply grok metaclasses to do that.
340    manuzhai soooo, is this were the #122 discussion is taking place?
341    adrian_h hugo-: What about a helper function for cases like yours? meta.create_model_from_dynamic_field_list(), except with a better name
342       rmunn hugo-: In other words, don't try it unless you're Dutch. :-)
343    adrian_h manuzhai: Yes, indeed
344       rmunn manuzhai: Yes.
345       hugo- rmunn: the main problem is that stuff like that would be code that only I would maintain because my coworkers _never_ will grok it ;-)
346    manuzhai rmunn: hey, don't fuck with the Dutch!!!
347       rmunn manuzhai: No no, it's a compliment.
348    manuzhai ok
349       hugo- rmunn: hey, I am living near the dutch border, so I am at least halfway competent ;-)
350    manuzhai so what are we actually talking about? :P
351       rmunn Only Guido van Rossum (and his brother) are smart enough to understand some of this stuff. :-)
352    adrian_h hugo-: What do you think of the helper function idea above?
353       hugo- adrian_h: if you find a better name ;-)
354    adrian_h create_model_from_dynamic_field_list_for_hugo()
355    adrian_h :)
356       hugo- lol
357       rmunn That's what, 30 characters long?
358       rmunn 40.
359    adrian_h At least this isn't PHP, where there's actually a performance penalty for using long variable names
360   Boffbowsh so glad to be moving over to python from php
361   Boffbowsh had to do a bit of php today, felt so... spaghetti like
362    adrian_h manuzhai: We're debating this syntax: http://django.pastebin.com/339441
363     Tybstar why the hell does viewcvs want TK??
364           * rmunn boggles. TK?
365    adrian_h The current question on the table is whether "class Meta" is a good name. It would conflict with a field named "Meta"
366       hugo- hmm. maybe if the mechanisms are made more transparent - define a set of functions to construct a model and then define the transformations that are used for transforming the class definition using _those_ functions into a model
367    manuzhai adrian_h: how is your current position?
368    adrian_h manuzhai: I'm getting more and more interested in the new syntax
369       hugo- that way the new syntax works nicely and somehugo with the need for programmatically creating models can use the documented "lower level"
370    adrian_h hugo-: That's a good solution
371    adrian_h A lower-level API for creating models
372    manuzhai adrian_h: that's good
373       hugo- actually that's the way Lispers often do this: build a set of base functions and define new syntax on top of it. They have macros, we have metaclasses for the syntax stuff
374       rmunn mmarshall's patch would need some serious rewriting, then.
375     Tybstar this is the suck.
376       rmunn Tybstar: Ouch. What distro?
377     Tybstar rmunn: it's a fedora machine
378     Tybstar i wish viewsvn worked
379   Netminder there's your problem :)
380     Tybstar heh
381       hugo- yikes. that's even worse than debians often-weird-dependencies :-)
382           * Tybstar wishes slashzero were here
383     Tybstar i just can't quite get viewsvn working
384       BleSS why i get this error? AttributeError: 'NoneType' object has no attribute 'status_code'
385           * rmunn *heart*s Synaptic
386    adrian_h BleSS: Your view has to return an HttpResponse object
387           * Notify: jacobkm is online (kornbluth.freenode.net).
388           * jacobkm (n=jacob@74.57.cm.sunflower.com) has joined #django
389   Boffbowsh BleSS: your get_object or whatever returned no object
390   Boffbowsh hence the Nojne
391   Boffbowsh *None
392    adrian_h That's a good case for a better error message.
393   Boffbowsh ahh, ok
394       rmunn adrian_h: Special-case check to see if None was returned from the view?
395    adrian_h rmunn: Yes
396   mmarshall rmunn: My patch is very simple; even stupidly simple now that the no-name-for-ForeignKeys thing is no longer needed.
397       hugo- since None is the implicit value for functions that are missing the return alltogether, I think that special case check would be usefull
398   Boffbowsh nn all
399           * proteusguy (n=proteusg@dsl027-163-201.atl1.dsl.speakeasy.net) has joined #django
400           * Boffbowsh has quit ()
401           * Dagur (n=dagur@dsl-196-5.hive.is) has left #django
402           * cmlenz has quit ()
403       BleSS adrian_h, whatever view has th reuturn an HttpResponse object? (my view simply add data to data base)
404    manuzhai BleSS: you should redirect then
405    adrian_h BleSS: Yes, every view has to return an HttpResponse object, so your users actually get a page. If you want to redirect, use HttpResponseRedirect('/path/to/new/page')
406       hugo- ok, so if the new syntax will be a combination of a documented model-creation API plus a compact class-based syntax on top of it, it get's a +1 from me
407       BleSS thanks
408    adrian_h hugo-: Yay
409       hugo- that should satisfy both the hacker and the maintainer in me ;-)
410           * jvoorhis (n=user@cpe-24-93-226-82.neo.res.rr.com) has joined #django
411    jvoorhis adrian_h: hi
412    adrian_h Hi jvoorhis
413    jvoorhis good work on the tutorial
414           * ljoramo (n=ljoramo@69-25-223-154.acsol.net) has joined #django
415    adrian_h jvoorhis: Thanks -- is everything going smoothly for you?
416    jvoorhis yes, except for python gotchas
417    adrian_h ah
418    jvoorhis a tuple is like a constant array, i guess
419   Netminder the sooner we make the change the better IMHO
420    adrian_h Netminder: Yes
421    adrian_h jacobkm: Hello
422    manuzhai adrian_h: could you or jacobkm look at my patch for #289?
423     jacobkm Howdy, adrian
424     jacobkm Looks like the logging bot has been broken for a few days :(
425    adrian_h Yeah :-(
426       rmunn Who set up the loglibrary logging in the first place?
427     jacobkm I did
428       rmunn So you're the one who can fix it (if it can be fixed).
429     jacobkm Yup
430     jacobkm I'm trying to figure out what's wrong right now.
431       rmunn I've got to go soon, but I'll save a copy of this IRC discussion in case anyone wants to look at what was said about #122.
432   Netminder I think loglibrary is having issues
433   Netminder I don't think there's anything we can do
434     jacobkm Hunh
435       rmunn Actually, most of it has already scrolled off the top of my scrollback buffer.
436    jvoorhis adrian_h: one thing i did not like was that the form on the details template has to be aware that it lives at polls/
437     jacobkm I was afraid of that.
438       rmunn Did anyone else manage to save the discussion from earlier?
439    manuzhai does anyone else think the CherryPy page on the wiki is pointless?
440    adrian_h manuzhai: Yeah, I just saw that and am tempted to delete it
441       hugo- rmunn: I can put the log from the discussion as a comment on #122 if you want
442    manuzhai I am, too
443    adrian_h rmunn: I've got the discussion
444    manuzhai please do so
445    manuzhai it seems like FUD
446       hugo- my scrollback buffer is big enough
447       rmunn Yes, please do.
448     jacobkm CherryPy page: gone
449    manuzhai hugo-: an attachment to #122 might be better
450    mrproper What is a closure & how does one use a closure in Python?  (I have an idea of closure from Javascript and event listeners)
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