in reply to
Code style advice: where to put "use" statements?
I have a feeling that the reason it is not covered in PBP or elsewhere is it's taken for granted that they should be up at the top.
As for putting it inside of a sub to indicate it is only used by that sub -- that could be confusing to less experienced Perl programmers and might cause it to get missed if someone is eyeballing the script for dependancies. It would be better to put it at the top and add a comment explaining where it is used.