$ perl -wMstrict -MData::Dump -e'       @{$a->{list}} =();  dd $a'
{ list => [] }
$ perl -wMstrict -MData::Dump -e'  for (@{$a->{list}}) {};  dd $a'
{ list => [] }
$ perl -wMstrict -MData::Dump -e'  my @x =  @{$a->{list}};  dd $a'
Can't use an undefined value as an ARRAY reference at -e line 1.
$ perl -wMstrict -MData::Dump -e'  my $x =  @{$a->{list}};  dd $a'
Can't use an undefined value as an ARRAY reference at -e line 1.
$ perl -wMstrict -MData::Dump -e'  my $x = $#{$a->{list}};  dd $a'
{ list => [] }