wish it were so simple:

$a = join'',map{ ('a'..'z')[rand 26] } 1 .. 1000;;

print "$-[0]: $1" while $a =~ m[(?:.{4})*(?=(aa..))]g;;
0: aawx
404: aawx
405: aadz
481: aadz

print "$-[0]: $1" while $a =~ m[(?:.{4})*(?=(gg..))]g;;

0: gghn
208: gghn
211: ggyj
955: ggyj

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In reply to Re^2: A regex that only matches at offset that are multiples of a given N? by BrowserUk
in thread A regex that only matches at offset that are multiples of a given N? by BrowserUk

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