That cool Massimo!
Thanks for this...
Richard
On Mon, Oct 21, 2013 at 3:26 PM, Massimo Di Pierro <
massimo.dipie...@gmail.com> wrote:
> Actually mine was an example. as_trees() does not dictate a model. The
> only requirement is that the model must have a self referencing field. You
> can call it any way you like it. You can pass its name as first argument of
> as_trees().
>
>
>
> On Monday, 21 October 2013 05:55:44 UTC-5, Niphlod wrote:
>>
>> ouch.... the easiest model to update, the worst to query.
>> I was going to post a plugin for threaded comments but then life kicked
>> in with lots of other requirements, and then other things got priority in
>> web2py.
>> I don't think this will be compatible with what I've done 'cause I use a
>> totally different model, but alas, this is better than no plugin at all.
>>
>> On Monday, October 21, 2013 5:57:00 AM UTC+2, Massimo Di Pierro wrote:
>>>
>>> It is a recurrent problem that is displays tree-like structures like
>>> threaded comments. For example:
>>>
>>> db.define_table('post',
>>> Field('parent_id','reference post'),
>>> Field('body'))
>>>
>>> where each comment has a body and a parent_id (parent_id==None for the
>>> root comment(s))
>>> We can populate the comments with some dummy data:
>>>
>>> def make_up_data():
>>> import random, uuid
>>> ids = [None]
>>> for k in range(100):
>>> ids.append(db.post.insert(**parent_id=random.choice(ids),
>>> body=str(uuid.uuid4())))
>>> if k==0:
>>> ids.pop(None)
>>> if db(db.post).isempty(): make_up_data()
>>>
>>> The new feature in trunk allows you to select the comments are organized
>>> them into trees.
>>>
>>> roots = db(db.post).select().as_trees(**)
>>>
>>> This returns a list of parent nodes. Each not stores its own children,
>>> recursively.
>>>
>>> Now you can print them all using a tree traversal:
>>>
>>> def show(row,n=0):
>>> return ' '*n+row.body+'\n'+''.join(**show(c,n+1) for c in
>>> row.children)
>>> print show(roots[0])
>>>
>>> Notice you can specify the name of the parent field:
>>>
>>> roots = db(db.post).select().as_trees(**parent_name="parent_id")
>>>
>>> Please let me know if you think this can be improved.
>>>
>>> --
> Resources:
> - http://web2py.com
> - http://web2py.com/book (Documentation)
> - http://github.com/web2py/web2py (Source code)
> - https://code.google.com/p/web2py/issues/list (Report Issues)
> ---
> You received this message because you are subscribed to the Google Groups
> "web2py-users" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to web2py+unsubscr...@googlegroups.com.
> For more options, visit https://groups.google.com/groups/opt_out.
>
--
Resources:
- http://web2py.com
- http://web2py.com/book (Documentation)
- http://github.com/web2py/web2py (Source code)
- https://code.google.com/p/web2py/issues/list (Report Issues)
---
You received this message because you are subscribed to the Google Groups
"web2py-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to web2py+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/groups/opt_out.
