I would “up” this a little and say that scripting languages “should” be slow in comparison to low level compiled languages. We want eg. runtime evaluation of multis dependent on type. For (cod) example:

  subset Even of Int where *  %% 2;
  subset Odd  of Int where * !%% 2;

  multi foo(Even $i) { ‘fizz’ }
  multi foo(Odd  $i) { ‘buzz’ }

  say foo for ^9;