A code reference doesn't know by what name it appears, and cannot since it might be anonymous, or it might have been assigned to multiple names throughout the filesystem. (A common example of that is when you import functions from a module - that function is now both in the module and in your namespace, which is its name?)

Therefore unless you want to start walking through the symbol table to see if any named function matches the function reference that you have, it doesn't have a name.

BUT if you really want, what you can do is use bless to give references a name (well it does more, but we can ignore the more), and then with no change in your dumping code, function references will now keep track of the names given. I wouldn't recommend this for serious use, but it could be handy while debugging.