That's really a bad idea in the general case, because it won't work if $k has a string terminator in it: 
sub emphasizePrint
{
  my $k = qq{"!!\n};
  return sub {
    my ($str) = @_;
    eval (qq{print "$str$k"});
    print STDERR "Error: $@" if ($@);
  }
}
__END__
Error: Can't find string terminator '"' anywhere before EOF at (eval 1
+) line 2.

[download]

In the general case this opens lots of holes, which can be a security risk.

I think that citromatik deliberately interpolated the variables at eval time, not prior to evaling the string.

In reply to Re^2: 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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