I obviously hadn't quite mastered combining positive lookahead and non-greediness (selflessness?) yet. Until now my solution was to use two statements:

    s{\[_(CELL|COLHEAD)_\] (.*)}{<$1>$2</$1>}g;
    s{\s*\[_(CELL|COLHEAD)_\]\s*}{</$1><$1>}g;
[download]

Here it's more complicated because there's several of these tags. It's lamer and slower than yours, so I'll gladly change it, thanks!

Pauses to think for a while... Hm, with that extra twist I just introduced (not fair, I know), maybe the two-step version isn't slower. Lookahead on something it doesn't know yet could get tricky, maybe.

    s,\[_(CELL|COLHEAD)_\]\s*(.*?)\s*?(?=\[_\1_\]|$),<$1>$2</$1>,g;

But it seems to work fine, and I don't think I care about speed anyway.

---

---

• Are you posting in the right place? Check out Where do I post X? to know for sure.
• Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:

  <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>

• Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.