protected function compileShallowJson(array $array, $vars)
 {
     $compiled = [];
     foreach ($array as $i => $hint) {
         $compiled[$i] = $this->compiler->compileString($hint, $vars);
     }
     return $compiled;
 }
 /**
  * @param NULL|int $seed
  * @return ScalarExercise
  */
 public function getExercise($seed = NULL)
 {
     $this->compiler->reseed($seed);
     return $this->compiler->compile($this->blueprint);
 }