Fellow Monks, I've recently tackled a code update project at my day job that involves scanning program code for some crummy stuff and replacing it with smart stuff. (The code is Business Basic, for those interested). At any rate, the bad code attempts to PRINT some ASCII terminal control characters that are better represented by a sequence that is not terminal-type dependent. An example line looks like:
10 PRINT "<29>This should be dim.<30>EThis should be reversed.<28>This
+ is bold."

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And so on. The pieces that look like <\d+> are what I'm interested in. What this should be replaced with is:
10 PRINT @(-38);"This should be dim.";@(-37);"This should be reversed.
+";@(-40);"This is bold."

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OK, no problem. So I set up a hash with keys in it like '<29>' and a value like '@(-38);'. And, using the /g switch of the pattern match operator, I can do:
while ($line=~/(<\d+>)/g) {
 next if ($1 eq '<30>');
 $line=~s/$1/$fix{$1}/;
}

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I've ignored the codes like <30>E because they are a slighty different pattern, and I want to keep the code simple so I can set up a similar loop for those.
The problem is those darn double quotes in the PRINT statement. As you can see from the desired output, regular text should be bracketed in quotes but those ASCII codes should be changed to the @ statments outside quotes!
So can anyone come up with either a pattern match or substitute operator to successfuly change the bad line to the good? I believe this could be done with pos() and index() but that would be a lot of repetition in the code, and slick RegEx's are so much nicer :)

Thanks for any ideas

In reply to Smart Search and Replacement with RegEx by shelob101

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