I refined my question a little more. I have a string of letters [ACGTacgtNn] from which I want to find a particular instance of a regexp, let's say: 
/ACCAAC[ACGTacgtNn]{6}CTA[ACGTacgtNn]{1}ATG[ACGTacgtNn]{1,2}GATGTT/

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I can do this just fine, but what if I want to match the above regexp with a tolerance of 2 mismatches for single characters. Below I have an example: 
$buf =~ m/(A)(C)(C)(A)(A)(C)([ACGTacgtNn]{6})(CTA[ACGTacgtNn]{1})(A)(T
+)(G)([ACGTacgtNn]{1,2})(G)(A)(T)(G)(T)(T)(?{
    print $-[0]," ",scalar@-,"\n";
    })(?!)/;

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this will print the position of the match in $buf, followed by 19 (the number of submatches). I want to be able to return a match from 17-19 submathes, not just all 19. Thanks. Vince

In reply to Re: non-exact regexp matches by vinforget
in thread non-exact regexp matches by vinforget

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