my @arr;
   push @arr, { xx=>\99 } for 1..2;
   my $arr2 = YAML::XS::Load( YAML::XS::Dump( \@arr ) );
   $arr2->[0]->{xx}='THIS VALUE IS MEANT TO CHANGE ONE ROW ONLY';
   say "NO WAY!" if $arr2->[0]->{xx} eq $arr2->[1]->{xx}; # which prints NO WAY! 

##</code><code>##

---
- xx: &1 !!perl/ref
    =: 99
- xx: *1