c:\@Work\Perl>perl -wMstrict -MData::Dump -le
"sub S { print 'oops...'; }
 ;;
 my $hr = { 'darn' => S,  'rats' => \S,  'nuts' => &S, };
 ;;
 dd $hr;
"
oops...
oops...
oops...
{ darn => 1, nuts => 1, rats => \1 }