Try:

foreach $item (@array){
   if(ref($item) eq 'ARRAY'){
      #It's an array reference...
      #you can read it with $item->[1]
      #or dereference it uisng @newarray = @{$item}
   }else{
      #not an array in any way...
   }
}
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look at the ref() function in perl, it tells you the type of ref you have.

Alternatively, you can use universal.pm

use UNIVERSAL 'isa';

foreach $item (@array) {

if (isa($item, 'ARRAY')) {
print "We've got an array!!\n";
}

}
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If there's a chance of wanting to catch bless'ed arrays, or dealing with psychologically nasty code, such as my $item=bless {}, 'ARRAY', then it's best to be paranoid and check if you can actually treat the item as an array.

The following code snippet shows a function that does this kind of check:

for my $item (@array) {
  print "We've got an array" if is_array($item);
}

sub is_array {
  my ($ref) = @_;
  # Firstly arrays need to be references, throw
  #  out non-references early.
  return 0 unless ref $ref;

  # Now try and eval a bit of code to treat the
  #  reference as an array.  If it complains
  #  in the 'Not an ARRAY reference' then we're
  #  sure it's not an array, otherwise it was.
  eval {
    my $a = @$ref;
  };
  if ($@=~/^Not an ARRAY reference/) {
    return 0;
  } elsif ($@) {
    die "Unexpected error in eval: $@\n";
  } else {
    return 1;
  }

}
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The reftype function in module Scalar::Util is good. It returns 'ARRAY' for any array reference, even if it's blessed.