sub int_monitor (\$ ) :lvalue {
  my $var=shift;
  print "$var\n";
  $$var
};

int_monitor(my $foo) = 14;
print "$foo\n";

(int_monitor my $bar) = 15;
print "$bar\n";

##</code><code>##

sub int_monitor (\$;$)  {
  my $var=shift;
  print "$var\n";
  $$var=shift if @_
};

int_monitor my $foo => 14;
print "$foo\n";