>perl -wMstrict -le
"use constant FOO => 'foo';
 ;;
 my %hash = (
   FOO() => 'ok',  FOO => 'oops',  +FOO => 'huh?',  'FOO' => 'yes',
   );
 ;;
 use Data::Dump;
 dd \%hash;
"
{ foo => "ok", FOO => "yes" }