Not true. It only requires a global instance of the object OR a pre-existing $someobj, not both.

Pre-existing:

sub create_closure {
   my ($obj) = @_;
   return sub { print($obj, $/); };
}


my $sub;
{
   my $existing_obj = 1234;
   my $sub = create_closure($existing_obj);
}
&$sub();  # Prints 1234, even though $existing_obj is out of scope.
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Global:

our $global_obj;

$global_obj = 1234;
my $sub = sub { print($global_obj, $/); };
$global_obj = 5678;
&$sub();  # Prints 5678.
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