I have run into a little problem in extracting information from a bunch of files. As I loop through all the files, I slurp each one in and then look for information matching certain criteria. For simplicity's sake, lets say that the file contents is

$fc = 'abcdfoofrobnicatebardefforspambazghi';

I then search for certain patterns in the file and capture them using a regex, say:

$re1 = qr/fo.*?ba./;

I capture them into an array for later analysis thus:

@excerpts = $fc =~ /$re1/g;

The above yields two entries in @excerpts: 

foofrobnicatebar
forspambaz

[download]

Later, when I get to analyzing the excerpts, I want to search each one for patterns within each match using almost the same regex with capture groups:

$re2 = qr/(fo.)(.*?)(ba.)/;

This gives me 

foo frobnicate bar
for spam baz

[download]

My question is this: The expressions I am really using are much more complicated in the two regexes, $re1 and $re2, and there are orders of magnitude more captures than the two shown here. If I make a change to one regex, I have to change the other. This can be a hassle in big ugly expressions, and I have already failed once to notice they were not in sync. It would be nice to have only one regex, but if I were to use the second expression in the first capture, I would get 

@excerpts = $fc =~ /$re2/g;

foo frobnicate bar for spam baz

[download]

Six entries in @excerpts

Having capture groups in a /g capture makes each capture group add an element to the array instead of the whole regex adding one. Is there an easier way than having two almost identical regexes? Can I have one regex with capture groups, but keep it from making each capture group create an array element under /g?

In reply to Behavior of /g when there are capture groups by ExReg

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