c:\@Work\Perl\monks>perl -wMstrict -MData::Dump=pp -le
"sub S { print qq{in S: args }, pp \@_; }
 ;;
 S(my $x = 'foo', my $y = 'bar');
 print qq{outside S: \$x == $x,  \$y == $y};
 ;;
 sub S ();
"
Prototype mismatch: sub main::S: none vs () at -e line 1.
in S: args ["foo", "bar"]
outside S: $x == foo,  $y == bar