Compare Devel::Refcount::refcount with Internals::SvREFCNT

refcounts.pl

#!/usr/bin/env perl

use v5.16;
use warnings;

use Devel::Refcount qw(refcount);

my $href = {};

say "BEGIN:"  . refcount($href);
say "SvREFCNT: ", Internals::SvREFCNT($href);

my $href2 = $href;

say "VAR:" . refcount($href);
say "SvREFCNT: ", Internals::SvREFCNT($href);

f1($href);
f2($href);

my $n1 = f3($href);
say "AFTER f3:" . refcount($href);
say "SvREFCNT: ", Internals::SvREFCNT($href);

my $n2 = f4($href);
say "AFTER f4:" . refcount($href);
say "SvREFCNT: ", Internals::SvREFCNT($href);
	

sub f1 {
	say "f1:" . refcount($_[0]);
}

sub f2 {
	my $v = shift;
	say "f2:" . refcount($v);
}

sub f3 {
	return { args => \@_ };
}

sub f4 {
	return { args => [@_]};
}