perldoc -f ref

ref returns the type being referenced, or false if it is not a refernce (you see empty string when we try to use it as a string):

use strict;
use warnings;

my $a = 123;
my $aref = \$a;
my @b = (1,2,3);
my $bref = \@b;

print "[" . ref($a) . "]\n";
print "[" . ref($aref) . "]\n";
print "[" . ref($b) . "]\n";
print "[" . ref($bref) . "]\n";
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You can also use UNIVERSAL->isa():

use strict;
use warnings;

my $a = 123;
my $aref = \$a;
my @b = (1,2,3);
my $bref = \@b;

print UNIVERSAL::isa($aref, "SCALAR") + 0, "\n";
print UNIVERSAL::isa($bref, "ARRAY") + 0, "\n";
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Why do people on this site insist upon bolding their replies? Bold is for emphasis. However, you seem to think that everything that isn't code in your post is worthy of emphasis. It's a reply. The OP will probably read it regardless of your bold and just piss off people like me who think it is bad etiquette. This bold thing seems to come in waves. I think the tide's coming back in. I guess it's time to finally add that css entry I've been meaning to do.

Update: poorly-formed HTML pisses me off as well. Please close your b tag somewhere.

Update 2: Hey, thanks.

antirice    
The first rule of Perl club is - use Perl
The ith rule of Perl club is - follow rule i - 1 for i > 1

if (ref $var eq 'SCALAR') {
  print "scalar\n";
} elsif (ref $var eq 'ARRAY') {
  print "array\n";
} elsif (ref $var eq 'HASH') {
  print "hash\n";
}
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