Regular expressions have always been a weak spot for me, and I've got a question that's got me stumped.

Here's the problem I'm trying to solve.

I have somwhat large articles of text (returned from a search), what I'd like to do is capture the word and X number of words before and after it while tagging the matching word in the captured text.

My inital thought was to try something like this. 
my $regex = \b(.{1,50})\b(?i)('.join("|",@words).')\b(.{1,50})\b';
my $expr = qr /$regex/; 

# Later              
my $matchtext;
while ($text=~m/$expr/g){
  $matchtext.= "...$1<font color=\"FF0000\">$2</font>$3...<br><br>" ;
}

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The problem I have is that if there is more than one term and they overlap, the nth term will not be annotated.

So my next thought is lookahead/lookbehind, but they don't capture. Is there a way to do this with a single regex?

Is a regex even the best way to do this?

Thanks,
-Lee

perl digital dash (in progress)

In reply to Regex: Matching around a word(s) by shotgunefx

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