>perl -wMstrict -le
"my @ra = (9, 8, 7, 6);
 ;;
 F(\@ra);
 ;;
 sub F {
   our @ydata;
   local *ydata = shift;
   print qq{pre-G: (@ydata)};
   G();
   print qq{post-G: (@ydata)};
   }
 ;;
 sub G { our @ydata = 'Gaaaahh!'; }
"
pre-G: (9 8 7 6)
post-G: (Gaaaahh!)