Nested tags

[Devin Asay]

On Jun 18, 2006, at 6:27 AM, Terry Vogelaar wrote:

> Hi all,
>
> I've got a scripting problem that seems ridiculously simple.
>
> I have to find the corresponding end tag in a HTML file with nested  
> <SPAN> tags:
>
> <SPAN class="FOOTNOTE">
> <SPAN Class="reference">
> origin
> </SPAN>
> <SPAN Class="quote">
> <SPAN Class="smallcaps">
> Text
> </SPAN>
> more text
> </SPAN>
> </SPAN>
>
> Some of the tags are nested. How do I find the end tag of each SPAN  
> tag? The tag on line 1 has its end tag on line 11, but the first  
> time it sees </SPAN> is on line 4...

Terry,

A few months ago I was trying to emulate browser-like html rendering  
and I needed a function like this. The function I wrote returns a  
list of all instances of the tag you tell it to search for. Once I  
got the list back I could do whatever I wanted with the tag pairs-- 
delete them, substitute formatting for tags, etc.

-- This function takes three parameters: (1) a string that describes  
the opening tab, eg., "<img"
--   (2) a string describing the closing tag, eg., "</img>" and (3) a  
string containing the html code
--   to be searched. It returns two items that indicate the beginning  
and ending character 
--   offsets of that tag.
function extractTag openTag, closeTag, htmlCode
   put offset(openTag,htmlCode) into openTagPosList
   if openTagPosList = 0 then return 0
   put offset(closeTag,htmlCode) into closeTagPosList
   put openTagPosList into openTagSearchStart
   put closeTagPosList into closeTagSearchStart
   put 1 into i
   repeat -- find all opening and closing tags
     put offset(openTag,htmlCode,openTagSearchStart) into  
openTagFoundChar
     if openTagFoundChar = 0 then exit repeat
     put openTagSearchStart + openTagFoundChar into openTagSearchStart
     put offset(closeTag,htmlCode,closeTagSearchStart) into  
closeTagFoundChar
     put closeTagSearchStart + closeTagFoundChar into  
closeTagSearchStart
     add 1 to i
     put openTagSearchStart into item i of openTagPosList
     put closeTagSearchStart into item i of closeTagPosList
   end repeat
   repeat with i = 1 to number of items in openTagPosList
     put "o" after item i of openTagPosList
     put "e" after item i of closeTagPosList
   end repeat
   put openTagPosList & comma & closeTagPosList into tagsList
   sort items of tagsList numeric
   return tagsList
end extractTag

Hope this works for you.

Devin

Devin Asay
Humanities Technology and Research Support Center
Brigham Young University