Note that if the strings being compared are equal, both JavaFan and jwkrahn's solutions yield a number for the first difference offset that is equal to the length of the string(s). 

>perl -wMstrict -lE
"my $s1 = 'abcdefg';
 my $s2 = 'abcdefg';
 ;;
 my $t = $s1 ^ $s2;
 ;;
 my ($f) = $t =~ /^(\x{00}*)/;
 say length $f;
 ;;
 $t =~ /^\0*/ && say $+[0];
"
7
7

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In reply to Re: If there a way to find the location of the first difference between two strings? by AnomalousMonk
in thread If there a way to find the location of the first difference between two strings? by flexvault

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