If you're using 5.004 or later (i think), then you just need to use Symbol

++! That's what I was looking for. Fortunately, it's in the core distribution.

It seems I was very close:

# from Symbol.pm
    # free all the symbols in the package

    my $leaf_symtab = *{$stem_symtab->{$leaf}}{HASH};
    foreach my $name (keys %$leaf_symtab) {
        undef *{$pkg . $name};
    }
[download]

But Symbol does a bit more than I did:

    # delete the symbol table

    %$leaf_symtab = ();
    delete $stem_symtab->{$leaf};
[download]

Which I didn't do, because it seemed that it didn't work at all. However, it probably didn't work in an rmdir way: there were still symbols in the table. (rmdir doesn't delete non-empty directories)

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