my $foo;
sub context :lvalue { $foo = wantarray ? 'list' : 'scalar' } 

context() x= 1;
print $foo;

__END__
scalar

##</code><code>##

use Data::Dumper;

my %foo = qw/ a 1 b 2 /;
@foo{qw/ a b /} x= 0;
print Dumper \%foo;

__END__
$VAR1 = {
          'a' => '1',
          'b' => ''
        };

##</code><code>##

\@foo{@list};