enum Sizes {

  Small,

  Medium,

}

​

switch (Number(Sizes.Small)) {

  case Sizes.Small:

    // 👇️ this runs

    console.log('size is S');

    break;

  case Sizes.Medium:

    console.log('size is M');

    break;

​

  default:

    console.log(`non-existent size: ${Sizes.Small}`);

    break;

}