use Data::Dumper;

my $ref = [];
push @{$ref}, qw(abcd efgh ijkl);

print Dumper($ref);

foreach my $test (@$ref) {
	$test = substr($test, 0, 2);
}

print Dumper($ref);

##</code><code>##

$VAR1 = [
          'abcd',
          'efgh',
          'ijkl'
        ];
$VAR1 = [
          'ab',
          'ef',
          'ij'
        ];