Your input is in $line and you're trying to transliterate $nuline without first assigning $line to $nuline. Compare your program with this:

while (my $line = <DATA>) {
    chomp $line;
    (my $nuline = $line) =~ tr/a-zA-Z/n-za-mN-ZA-M/;
    print "$nuline\n";
}

__DATA__
me
you
someone else

[download]

Output:

zr
lbh
fbzrbar ryfr

[download]

update:: output added

In reply to Re: Problem using transliteration to modify a variable... by FunkyMonk
in thread Problem using transliteration to modify a variable... by cgmd

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