[pmwiki-devel] Markup routine for style questions

[Patrick R. Michaud]

On Fri, Oct 26, 2012 at 12:19:06PM -0400, W Randolph Franklin wrote:
> Markup('^>>', '<table',
>   '/^>>(.+?)<<(.*)$/',
>   '(:div:)%div $1 apply=div%$2 ');
> Markup('^>><<', '<^>>',
>   '/^>><</',
>   '(:divend:)');
> 
> My questions:
> 
> 1. Why is > used instead of > in the search pattern?   Since the page
> being edited contains >, this should always fail.

One of the first markup rules that PmWiki performs is to convert all
<'s and >'s to html entities to minimize injection attacks.

> 2. Is there a reason that the pattern name is ^>> ?  Does the leading ^
> do anything in the pattern name?

Pattern names are just identifiers, so it doesn't do anything.
But someone reading the rule or seeing the identifier in a list
would be informed that it's a markup that only applies at the beginning
of lines.

> 3. In  '/^>>(.+?)<<(.*)$/',   what is the final (.*)$ for?
>  The documentation does not mention trailing text after the <<.

I'm not sure why there's a trailing (.*)$ there.  There must've been
something that failed when it wasn't there, though.

> 4. In  '(:div:)%div $1 apply=div%$2 '),   what do the percents do?  This
> looks like a nested div, why?

This rule is taking markup of the form

    >>red something<< text

and converting it to markup of

    (:div:)%div red something apply=div%  text

This then gets processed by the standard (:div:) and WikiStyle
markup rules.  The percents are just the standard WikiStyle markup, 
with the first 'div' causing standard div styles to be applied, 
and the 'apply=div' being thrown in to force application of the style 
to the entire <div> element that is ultimately generated.

> 5. Finally how do I set styles inside list items?   >><< and (:div:)
> terminate the list because they work only in column 1.   Percents appear
> to have an implementation error, where using apply causes the style to
> be ignored.   I need to use apply=p to avoid other formatting problems.

You might want %item%, as in:

    * First item
    * %item red%  This item is red
    * This item is normal
    * %item blue%  This item is blue

>   --------------------
> 
> In a list item, percents work, boxing each line.  > < and div do not, if
> indented, or terminate the list, if not indented.

Technically, percent WikiStyles don't box an entire line -- they 
box content until either the end of the line or the next WikiStyle.

> # In a list item, using any 'apply' inside percents causes the style to
> be ignored.
> 
>   %blue%   blue  
> 
>   %red apply=p ignored%   red apply=p ignored  
> 
>   %green%  green  

For a variety of reasons, PmWiki doesn't wrap the content of list items
as <p> paragraph elements, even when surrounded by blank lines.  Thus the
'apply=p' has no effect inside of a list item because there's no 
<p>...</p> available for it to apply the style to.

(One reason PmWiki doesn't put list item contents into <p>...</p> tags
is because <p> paragraphs in HTML 4 aren't allowed to have nested block 
elements, such as nested lists.  I decided nested lists were more
important and went that direction.)

What sort of "other formatting problems" are you needing to
avoid by using 'apply=p'?

Pm