Another tricky (at least in my book) regex question, that unfortunately looks deceptively simple. Here's some code...

$test = "abc";
while $test =~ m/(a(b?c)?)/g print "$1\n";

[download]
Ultimately, I need the regex to produce the following output:

a
ab
abc

Using greedy quantifiers, I'm currently getting only the single match "abc", and if I switch to using reluctant quantifiers, I only get the single match "a".

Of course, I understand why that's the case. The matcher exits as soon as it has found a match (either greedily or reluctantly) and then quits, without trying to find another match.

But for my application, I really need to find all instances of all matches, even if they occur within other matches.

Now, before you answer the question, I know what a lot of you are going to say: "use $2 and $3".

Unfortunately, that's not going to work. The regular expression isn't hard coded into the application. Instead, it's dynamically generated from a list of (possibly thousands) of search terms. In fact, my real code uses non-capturing groups in the interior of the expression, so the only captured group that I can access is $1.

Any ideas?

--BenjiSmith

In reply to Regex Subexpressions by BenjiSmith

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