For the first case, I'd add an additional check:
if( ref($obj) && UNIVERSAL::isa($obj,'Class') ) {
$obj->invoke_method();
}
since UNIVERSAL::isa("main",'main') returns true even though "main" is not an object; UNIVERSAL::isa() works on class names as well.
For your second test, I'd go a quite different route:
if( ref($obj) && UNIVERSAL::isa($obj,'UNIVERSAL') ) {
or, just to be shorter:
if( ref($obj) && UNIVERSAL::can($obj,'can') ) {
# or
if( ref($obj) && UNIVERSAL::can($obj,'isa') ) {
You can also do:
use UNIVERSAL qw( isa can );
to make the above tests much shorter to write (allowing you to drop "UNIVERSAL::" in each).
This all partially illustrates why it was a mistake for ref() to deal with both reference nature and blessedness nature. ref() should only return things like 'ARRAY' while a separate function, blessed() should tell you whether the item is a blessed reference or not (and probably return the package into which it was blessed, though using such information directly is usually a bad idea).
-
tye
(but my friends call me "Tye")