Another variant I haven't seen; processing through the list backwards lets you stop as soon as you find an 'A' or 'B'. (That does mean this won't work if setting that variable is just a proxy for a more complex process with side-effects that really does need to be executed for each letter in the string.)

#! /usr/bin/perl

$string="A111B111A111B111";
$yes_or_no="no";

$yes_or_no = '';
for (my $x=1; $x<=length($string); $x++) {
    my $c = substr($string, -1 * $x, 1);
    $yes_or_no = "yes" if ($c eq 'A');
    $yes_or_no = "no" if ($c eq 'B');
    last if $yes_or_no;
}
print "yes_or_no $yes_or_no\n";

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In reply to Re: Change variable multiple times within a single string? by dd-b
in thread Change variable multiple times within a single string? by JTomb

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