Hi, I novice in perl but I do think to do something like it: 
$_ = 'aaabbbbbbbbbbbbbccccccccccccccccccccc'; 
print "$1|$2\n" while (m[(.)(?>\1+)(.)]g);

[download]
Output: a|b b|c

In reply to Re: Regex backreference problem. by Anonymous Monk
in thread Regex backreference problem. by BrowserUk

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