Typescript，如何摆脱这些switch语句

Question

Typescript basic question;

loadedExercise.exercise contains an exercise that has been loaded from an API. After the load, I apply some computations to that loaded exercise and I leave them inside translationsAudiosOthers . Then I create a number of fields containing statistics that are different for each type of exercise. visitedBranch is a formal parameter that a function containing the mentioned switch statement receives, which indicates the specific statistic field of that exercise that I want to retrieve so I can show it in a react UI

Given a switch/case like this, how would you improve it? I don't want to maintain it in case I add more exercise types and I'm 100% sure there must be a better way of doing this using generics or similar

switch (loadedExercise.exercise.type) {
      case ExerciseTypes.typeA:
        return (loadedExercise.exercise.translationsAudiosOthers as TypeAExerciseLocalizations)[
          visitedBranch as TypeAStatBranches
        ];

      case ExerciseTypes.typeB:
        return (loadedExercise.exercise
          .translationsAudiosOthers as TypeBExerciseLocalizations)[
          visitedBranch as TypeBStatBranches
        ];

      case ExerciseTypes.TypeN:
        return (loadedExercise.exercise
          .translationsAudiosOthers as TypeNExerciseLocalizations)[
          visitedBranch as TypeNStatBranches
        ];
    }

Please note I am trying to avoid using any as in

return (loadedExercise.exercise.translationsAudiosOthers as any)[
          visitedBranch as any
        ];

as I lose autocomplete and I know we must avoid using any everytime we can.

Answer 1

A simple workaround is to create a interface to map out the types you want(assuming ExerciseTypes is a enum):

interface ExerciseTypeToLocalizations {
    [ExerciseTypes.typeA]: TypeAExerciseLocalizations;
    [ExerciseTypes.typeB]: TypeBExerciseLocalizations;
    [ExerciseTypes.typeN]: TypeNExerciseLocalizations;
}
interface ExerciseTypeToStatBranches {
    [ExerciseTypes.typeA]: TypeAStatBranches;
    [ExerciseTypes.typeB]: TypeBStatBranches;
    [ExerciseTypes.typeN]: TypeNStatBranches;
}

// instead of a switch statement
return (
    loadedExercise.exercise.translationsAudiosOthers 
    as ExerciseTypeToLocalizations[typeof loadedExercise.exercise.type]
)[visitedBranch as ExerciseTypeToStatBranches[typeof loadedExercise.exercise.type]]

With what was presented, this is the best I can do. If you can provide more context to the code I'm sure there is a more elegant way using generics.