my @arr = qw( and you will be pleased with the results );
my $mask = 0x2b;

sub mask_array (\@$) {
  my( $arr, $mask ) = @_;
  my @want = split '', unpack( "b*", $mask );
  return @{ $arr }[ grep { $want[ $_ ] } 0..$#{ $arr } ];
}

my @result = mask_array @arr => $mask;