Yeah, I see the argument for making it a warning.

Detecting this case is complicated, though. Unlike pseudo-state variables, it's not a shaky part of syntax and composition and implementation. At best, you might be able to express that a lexical variable appears to be used only once, but I can still imagine a bizarre module interface which closes over the using scope's lexical.

I can still imagine a bizarre module interface which closes over the using scope's lexical

I can, too; but I tried, and I don't think it can be done -- at least not without resorting to something in the B namespace. You could probably do it, though. ;-)

I reckon we are the only monastery ever to have a dungeon stuffed with 16,000 zombies.

Doesn't keeping the elements in @_ basically have the same effect since they are aliases to the values in the use statement?

package Set;
sub import
{
  our $var = \$_[1];
}
1;
[download]

With this module, perl -e "use Set (my $x = 6,); $$Set::var++; will work but perl -e "use Set (6,); $$Set::var++;
will fail because "Modification of a read-only value attempted at -e line 1."

> resorting to something in the B namespace.

That's my plan ... ;)

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!}