use warnings;
use Math::BigInt;
use strict;

use Inline C => Config =>
    BUILD_NOISY => 1,
    USING => 'ParseRegExp';  


use Inline C => <<'END';

int is_ref(SV * x) {
    if(SvROK(x)) return 1;
    return 0;
}

int is_obj(SV * x) {
    if(sv_isobject(x)) return 1;
    return 0;
}

END

my $undef;
my $ref = \$undef;
my $obj = Math::BigInt->new(0);

for($undef, $ref, $obj) {
   print is_ref($_), " ", is_obj($_), "\n";
}

# Output:
# 0 0
# 1 0
# 1 1