in reply to Re^4: Regex for matching n-fold repititions of arbitrary characters
in thread Regex for matching n-fold repititions of arbitrary characters

maybe that's clearer:

$ perl -e 'print $1,$2,"\n" while ( "aabbaab" =~ /(.)(\1)/g )'
aa
bb
aa

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or 
$ perl -e 'print $&,"\n" while ( "aabbaab" =~ /(.)\1/g )'
aa
bb
aa

[download]

Cheers Rolf

In Section Seekers of Perl Wisdom