my $phone = '1234567890';

# convert alpha mnemonics
$phone =~ tr/A-PR-Z/222333444555666777888999/;
$phone =~ tr/a-pr-z/222333444555666777888999/;

# get rid of any nondigits
$phone =~ s/\D//g;

# format
$phone =~ s/^(\d{3})(\d{3})(\d{4})$/{$1) $2-$3/;
$phone =~ s/^(\d{3})(\d{4})$/$1-$2/; # no AC
print $phone, $/;