Assuming you want every element of your array to match then you can simpy use a grep e.g

my @array1 = qw( foo bar baz );
my @array2 = qw( foo b4r baz );

for my $a (\@array1, \@array2) {
  print "invalid: @$a\n"
    if grep !/^[a-z]+\z/, @$a;
}

__output__

invalid: foo b4r baz
[download]

HTH

_________
broquaint