2011/6/28 Morten Wang <nettrom@gmail.com>

2: Using functions instead of strings as the replacement in sub(). If you're looking to do a fair amount of conditional logic in your replacement, it might be more easily written by having a function do it, rather than attempt to do it all with a regex.

My $.02.

Thank you for this great idea that is worth much more than $.02. :-)
I can tell that my problem is completely solved now, much better than I had hoped previously.
I am glad to announce this small guide to functions which is the result of my last two day's work:
http://hu.wikipedia.org/wiki/Szerkeszt%C5%91:Bin%C3%A1ris/Fixes_and_functions_HOWTO
This shows not only an example of a complicated replacement, but also the way to compare the match to the whole article (removing redundant links), or generating a long fix by means of a function. Another example is how to choose between two options for replacement during runtime (when you cannot decide it in coding time without a text environment).