Well, sadly (or happily) the copy function also works with a directory as the 2nd parameter, copying the 1st parameter into the directory given by the 2nd - and not just file to file. Furthermore, the module gives the possibilty to export functions named 'cp' and 'mv', just like corresponding *nix functions.

These factors make it (sadly!) more probable that copy is assumed to do something it does NOT do, i.e. copy @files, $dir.

Btw, move has the same problems, simply moving its 1st onto its 2nd parameter, silently ignoring any other arguments.