my $op = @_ ? ($seen{lc($field)}++ ? 'PUSH' : 'SET') : 'GET';

##</code><code>##

$ perl -Mstrict -Mwarnings -le '
    my $x = 1;
    print $x++;
    print $x;

    my $y = 2;
    print ++$y;
'
1
2
3

##</code><code>##

my @return_values = function(@args); # wantarray TRUE
my $return_value  = function(@args); # wantarray FALSE