Take the following (contrived) snippet for example.

my @array = (1, 2, 3);
my $aref = \@array;
showarray($aref);

my $text = 'some text';
my $ref = \$text;
my $blessed = bless($ref, 'ARRAY'); # bless the scalar reference into 
+class ARRAY
showarray($blessed);

sub showarray {
  my $aref = shift;
  local $\ = $/; # set the output record seperator
  return if (!UNIVERSAL::isa($aref, 'ARRAY'));
  print ref($aref), ": @$aref";
}

__DATA__
ARRAY: 1 2 3
Not an ARRAY reference at reftype.pl line 14.
[download]

Oops! How'd a scalar reference sneak by? (We really wanted to print $$aref; in this case.)

For one thing, you can use B::svref_2object (thanks diotalevi!):

use B;
sub refcheck {
  my $ref = shift;
  return ref(B::svref_2object($ref)) =~ /B::(\w+)/;
}
[download]

This will return the underlying C structure type but there are problems with this method (at least for me). Every time I try to use one of the B::C_Structure methods it results in a core dump. (B::PVMG::SvSTASH($object), B::PVLV::TYPE($lref), etc...)

You could simply strip off the excess information:

sub reftype {
  my $ref = shift;
  $ref =~ s/\(.*\)$//; # get rid of the (0x0000000) portion of the ref
+erence
  $ref =~ s/^.*=//;    # get rid of the CLASS= portion of the referenc
+e
  return $ref;
}
[download]

Although I'm sure this has some major drawbacks as well.

And this brings me back to my original question. How do you determine the true type of a reference?