Update: as stated before, I misread the question. There is no problem with Skeeve's solution, as it does what is stated.

Because I couldn't get Skeeve's to work on my strings, I did my own version, which should work: 

my $string = 'aaabcdabcddddddefgg';
$string =~ s/((.)(?(?=\2{2,})\2+))\1/$1/g;
print "$string\n";

[download]

I used the 'if 2 or more of the previous string' swallow them (prior to the backtrack, but anyhow), as it wouldn't work with duplicates when two or three were back to back, and * wasn't the solution, either.

Also to note, this 'rounds up', so if there are three back to back, two will remain (3 / 2 = 1.5, rounded up to 2).

In reply to Re: Replacing with multiple occurrences. by perlguy
in thread Replacing with multiple occurrences. by maithree

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