[Framework-Team] Re: wicked stuff

[whit]

Martijn Pieters wrote:
> On 7/16/07, Martijn Pieters <mj-a5Jd59zECFiB+jHODAdFcQ at public.gmane.org> wrote:
>> If the one-group limitation were removed, the pattern would be:
>>
>> pattern = re.compile(
>>     # Opening brackets or parens
>>     r'(?: (?P<parens>\(\() | \[\[ )'
>>
>>     r'(?P<text> [\w\W]+?)'                  # the text between the
>> brackets or parens)
>>
>>     # Closing brackets or parens
>>     r'(?(parens) \(\( | \[\[)', re.X)
>>
>> which will have a 'parens' and a 'text' group, and split and findall
>> will have to be re-thought.
> 
> Looking at the code, I realized we could easily do this in the
> WickedFilter class. The following overrides would help us deal with
> the additional pattern information:
> 
> import itertools
> 
>     def findall(self, value):
>         result = []
>         for groups in super(WickedFilter, self).findall(value):
>             result.append(groups[1])
>         return result
> 
>    def chunks(self):
>         chunks = super(WickedFilter, self).chunks
>         # every 2nd entry is the parens group, so filter out by
>         # grabbing every 1st and 3rd
>         firsts = itertools.islice(chunks, 0, None, 3)
>         thirds = itertools.islice(chunks, 2, None, 3)
>         result = []
>         # then append every 1st and 3rd to a list
>         map(result.extend, itertools.izip(firsts, thirds))

any difference between this and:

for slice in itertools.izip(firsts, thirds):
     result.extend(slice)

?
>         return result
> 
> I still have to deal with the fact that super(WickedFilter,
> self).chunks doesn't actually work (it's a property), but I can work
> that out too. Should I continue down this path?
> 
> Once this works, you can mix [[one format]] with the ((other format))
> in one document.
> 

there may be a simpler juncture for getting the desired effect.

the filter is run by a subscriber, and running it twice (once for each 
desired pattern) would be trivial, rather than pushing additional 
complexity into the filtering classes.  This would happen for both the 
findall call that is part of the storing event and the split call that 
is part of rendering.

Plone would use these special subscribers and if folks just wanted 
either/or behavior, they could disable them and use the old subscribers.

I'll take a look at this tomorrow.

-w



-- 

------ d. whit morriss ------
- senior engineer, opencore -
- http://www.openplans.org  -
- m: 415-710-8975           -

"If you don't know where you are,
  you don't know anything at all" 


Dr. Edgar Spencer, Ph.D., 1995