in reply to URI Inheritence
You should be able to use AUTOLOAD to implement method pass-through. I've done this in similar contexts. You basically build the AUTOLOAD method in your new class to say, "If the URI::URL object I contain has the method being called, then call it. Otherwise raise an exception."
For the scalar context issue, I believe that URI::URL overloads the "stringify" operator using operator overloading. Your new class could do the same thing if that's the case.
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