sub auth {
    my ($uname, $passwd, $dbsecret, $salt); 
    $uname = shift;
    $passwd = shift;
    ...
}

##</code><code>##

sub auth {
    my ($self, $uname, $passwd) = @_; 
    my ($dbsecret, $salt);
    ...
}

##</code><code>##

ref new Foo      or warn "example 1 is not an object\n";
ref new Foo->foo or warn "example 2 is not an object\n";

package Foo;
sub new { bless {} }
sub foo { "foo" }