[pmwiki-users] Pagelists of multiple linkbacks

[Christian Ridderström]

On Thu, 14 Aug 2008, Patrick R. Michaud wrote:

> On Mon, Aug 11, 2008 at 01:15:22AM +0200, noskule wrote:
>>> This is a planned feature but it doesn't exist yet.  On
>>> http://www.pmwiki.org/wiki/PmWiki/RoadMap it's given as
>>> "Allow link= option to do wildcards".

I very recently came across a use case for this...

We use categories such as 'ToDo', 'ToDo-Christian', 'ToDo-Anders' to tag 
pages that contain things that need to be done. Or maybe the entire page 
is just a to do list. The point is that many pages have these tags.

The sidebar then contains the link [[!To do]], i.e. a link to the page 
Category.ToDo, which of course lists all pages that contain the tag 
'ToDo'.  However, since we don't want to clutter sidebar with all the 
links [[!ToDo-Christian]], [[!ToDo-Anders]], these category pages are 
listed on the page Cateogry.ToDo. In other words, Category.ToDo contains:

 	(:pagelist group=Category name="Category.ToDo-*" :)

However, what we would also like to do is to add:

 	(:pagelist link="Category.ToDo-*" :)

since that would allow us to list all pages that in some sense need to be 
acted upon.

Note that I actually tried the above, thinking it would work and was very 
confused that it didn't... It wasn't until I read Patrick's post that I 
realized the functionlity isn't implemented yet.

We currently use the workaround that any page that is tagged with 
[[!ToDo-<x>]] must also be tagged with [[!ToDo]].


Writing the above, I realize that a better approach to tagging the pages 
might be using page text variables. In other words, for each to be tagged, 
add something like:

 	(:todo: Christian:)

Then it's just a matter of searching for all pages that have the PTV 
'todo' set....

Maybe tags should really be a special case of PTV, or rather that tags and 
categories should be implemented via PTV?

>>> However, I'm seriously considering Christian Ridderström's
>>> suggestion for being able to do set operations on pagelists:
>>>     (:pagelist link=Category.Personal     save=list1 :)
>>>     (:pagelist link=Category.Professional save=list2 :)
>>>     (:pagelist from=list1+list2 count=15 list=blog order=-ctime :)
>>>
>> hm, what would be the benefit/usecase  of this method, compared to
>> wildcards?  The only thing I see is that it isn't possible to exclude
>> categories.
>
> The biggest benefit is that this is easier to implement, plus it allows 
> greater flexibility than simple wildcards in links.  For example, it 
> would be possible to say arbitrarily complex things like "all pages in 
> category ABC that aren't on trail DEF" and the like.

As a concrete example, with the above functionality I could ask to find 
all 'todo'-pages, except those tagged with e.g. 'Todo-Anders'.

Best regards,
/Christian

-- 
Christian Ridderström, +46-8-768 39 44            http://www.md.kth.se/~chr