for(@options) {
   my($sign, $name, $value)=/[+-]([[\w]&&[^\d]]\w+)(?:=(.*))?/s;
   # this looks like a typo - there should be parens around
   # the [+-]?
   my $targ := ${$Exporter::From::{$name}};

   given($sign) {
      when('+'): {
          if(defined $value) {
              $targ=$value;
          }
          else {
              $targ is true;
          }
      }

      when('-') {
          if($targ.props{true}) {
              $targ is false;
          }
          else {
              undef $targ;
          }
      }
   }
}