let me ask you further:) I tried the code below $_="AHAAHKAKADL"; while ( /^(.)*(H)(.)*(K)(.)*(D)(.)*$/gx ) { print $1."\n"; print $2."\n"; print $3."\n"; print $4."\n"; print $5."\n"; print $6."\n"; print $7."\n"; print "-------\n"; # Restart the checking at one character after the match started. pos() = $-[0] + 1; } but that didn't work ask I expected. Actually my intention is dividing up the sequence in all combinations with patterns(these can be regex with willcards and all sort of-and the numberof patterns depends the user input) and keep the positions of the macthes of positions and length of the all patterns and the substrings in between. So I thought may be I could put them in a single pattern as the following: /^(.)*($pat1)(.)*($pat2)(.)*($pat3)(.)*$/ and match these to the whole sequence to extract the macthes and substrings in between, before and after. so above example is a simple case where patterns are single character. i would really appreciate any new point of view. thanks