[pmwiki-users] Re: Undesired space combined with (:if ...:)

[Patrick R. Michaud]

On Sun, Aug 07, 2005 at 09:50:56AM +0200, chr at home.se wrote:
> Just a thought... would it make sense to do an 
> initial conversion step that replaces blank lines with a special 
> marker/markukp? Then it doesn't matter if later blank lines are created 
> in intermediate steps, since you'll still be able to separate these from 
> the initially blank lines. 

I looked into this possibility once and decided it doesn't quite work.
But thinking about it more, perhaps it can.  The problem is knowing 
when to do the conversion step -- consider:

     Some text
     (:include SomePage:)
     More text

If we do the blank-line markers only once before the (:include:), 
then the included text's blank lines aren't marked.  If we do it
after an (:include:) has been processed which is what currently
happens), then the (:include:) itself generates extra blank lines 
that get marked.  More directly, consider:

    Text
    (:if false:)
    Text
    (:ifend:)
    More text
    (:include SomePage:)
    Still more text

The processing basically goes like:

    1.  Mark blank lines (there are none, initially)
    2.  Process the (:if:)...(:ifend:).  This results in an unmarked
        blank line, so far so good.
    3.  Process the (:include:)
    4.  The (:include:) requires reprocessing the text, to mark its
        blank lines and process any [=...=] and (:if:) markups in
        the included text, which ends up marking the blank line
        that formed in step 2.

The answer appears to be to have step 4 do the reprocessing of previous
markups only on the included text, but it's not entirely that simple.
However, the possibility I hadn't considered until now is to do the
marking of blank lines only on the included text, and then start
the reprocessing from the top.  That might work.

> >  	* Item A
> >  	(:if false:)* Item never shown
> >         (:ifend:)* Item B
> 
> I don't understand why you place extra space in front of (:ifend:)?

Well, I didn't -- the first two lines have a tab, the last used spaces,
so they don't appear to align properly when quoted.  They aligned
properly in my original.

> > This is also in keeping with the way to do multiple conditions:
> > 
> > 	* Item A
> > 	(:if auth edit:)* Item B
> >         (:if auth attr:)* Item C
> >         (:ifend:)
> 
> Um... I don't quite what you mean. I thought the above is more like
> 	* Item A
> 	(:if auth edit:)* Item B
> 	(:elseif auth attr:)* Item C
> 	(:ifend:)
> 
> in which case the indentation doesn't make sense to me. I'd only use 
> indentation if it was possible to have nested conditions.

PmWiki doesn't have (:else:) in any form.  What you see as (:elseif:)
is really more like

    * Item A
    (:if auth edit:)* Item B
    (:ifend:)(:if auth attr:)* Item C
    (:ifend:)

Each (:if:) automatically terminates any previous (:if:).

Pm