this would also work 
$var = 'bat';
if ($var =~ /^[bat]{3}$/) { print "match"; } else { print "fail"; }

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since you want only those letters to exist, check from beginning to end that word for each letter, the {3} should be the number of letters in that word

In reply to Re: regular xpression stuff by Parham
in thread regular xpression stuff by Anonymous Monk

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