>perl -Mstrict -wle"my $r; my @x; @x=@$r; print $r"
Can't use an undefined value as an ARRAY reference at -e line 1.

>perl -Mstrict -wle"my $r; my @x; @$r=@x; print $r"
ARRAY(0x225280)

##</code><code>##

>perl -Mstrict -wle"my $r; my @x = map{ $_ } @{ $r }; print $r"
ARRAY(0x225258)

##</code><code>##

>perl -Mstrict -wle"my $r; my @x; for(@$r){} print $r"
ARRAY(0x225280)

>perl -Mstrict -wle"my $r; my @x; sub{}->(@$r); print $r"
ARRAY(0x225280)