gistfile1.pl

use Devel::Peek;
#use Data::Printer use_prototypes => 0, return_value => 'pass';
#use Data::Printer use_prototypes => 1, return_value => 'pass';
my $foo = \*STDIN;
Dump(p $foo);

with use_prototypes => 0:
*main::STDIN  (read/write, layers: unix perlio)
SV = PVGV(0x7f8e3a91aea0) at 0x7f8e3aa25f30

with use_prototypes => 1:
\ *main::STDIN  (read/write, layers: unix perlio)
SV = PVMG(0x7f8c74193a60) at 0x7f8c740c9588