hasparus · August 4, 2019 13:20 · hasparus · Aug 4, 2019
diff --git a/exhaustive-switch.ts b/exhaustive-switch.ts
 function exhaustive(x: never): never {
  throw new Error(`
    Unreachable default case.
    ${x} is not assignable to type never.
  `)
 }

 type Fruit = "apple" | "banana" | "mango";

 declare const fruit: Fruit;

 switch (fruit) {
  case 'apple':
    break;
  case 'banana':
    break;
  default: exhaustive(fruit); // Argument of type '"mango"' is not assignable to parameter of type 'never'.
 }
	function exhaustive(x: never): never {
	throw new Error(`
	Unreachable default case.
	${x} is not assignable to type never.
	`)
	}

	type Fruit = "apple" \| "banana" \| "mango";

	declare const fruit: Fruit;

	switch (fruit) {
	case 'apple':
	break;
	case 'banana':
	break;
	default: exhaustive(fruit); // Argument of type '"mango"' is not assignable to parameter of type 'never'.
	}