Eh, no. shift || DEFAUTL_ADDR will do just fine, as a trivial example would have shown:

$ perl -wle 'use constant DEFAULT_ADDR => "127.0.01";
my $address = shift || DEFAULT_ADDR; print $address' 192.168.1.1
192.168.1.1
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It's always wise to test your code before giving advice, but it's quite unwise to *not* test code you're claiming needs to be done differently.