DB<5> l
20  sub new
21  {
22      # Check for common user mistake
23:     Carp::croak("Options to LWP::UserAgent should be key/value pairs, not hash reference") 
24          if ref($_[1]) eq 'HASH'; 
25  
26:     my($class, %cnf) = @_;
27  
28:     my $agent = delete $cnf{agent};
29:     my $from  = delete $cnf{from};