The problem is not that $k is garbage collected, but that it's not included in the closure. Actually your first sub doesn't return a closure at all, because no variables from the outer scope are enclosed (at compile time) in the anonymous sub at all.

If you can in your case, you could use the non-string form of eval: 

sub emphasizePrint
{
  my $k = "!!\n";
  return sub {
    my ($str) = @_;
    eval {
        print "$str$k"
    };
    print STDERR "Error: $@" if ($@);
  }
}

[download]

If that isn't applicable in your case I know no other way around than mentioning the variables in the closure once.

In reply to Re: Scope problem in closures with an eval statement by moritz
in thread Scope problem in closures with an eval statement by citromatik

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