Valid append 1
$VAR1 = 1;
$VAR1 = 2;
$VAR1 = 3;
$VAR1 = 5;
$VAR1 = 6;
$VAR1 = 7;
$VAR1 = 9;
$VAR1 = 10;


Valid append 2
$VAR1 = 'foo';
$VAR1 = 'bar';
$VAR1 = 'baz';
$VAR1 = 'zab';
$VAR1 = 'rab';
$VAR1 = 'oof';
$VAR1 = 1;
$VAR1 = 2;
$VAR1 = 3;


Invalid append 1
$VAR1 = 1;
$VAR1 = 2;
$VAR1 = 3;
$VAR1 = 'foo';
$VAR1 = 'bar';
$VAR1 = 'baz';
$VAR1 = sub {
            use warnings;
            use strict 'refs';
            return $start <= $end ? $start++ : undef;
        };


Invalid append 2
$VAR1 = 'foo';
$VAR1 = 'bar';
$VAR1 = 'baz';
$VAR1 = sub {
            use warnings;
            use strict 'refs';
            return $start <= $end ? $start++ : undef;
        };
$VAR1 = sub {
            use warnings;
            use strict 'refs';
            return $start <= $end ? $start++ : undef;
        };

Invalid append 3
$VAR1 = 'foo';
$VAR1 = 'bar';
$VAR1 = 'baz';
$VAR1 = sub {
            use warnings;
            use strict 'refs';
            shift @list;
        };

Invalid append 4
a