这段程序会输出什么?
TypeScript
type Result<Value> =
| { ok: true; value: Value }
| { ok: false; error: string };
function values<Value>(items: Result<Value>[]): Value[] {
return items.flatMap((item) => item.ok ? [item.value] : []);
}
const attempts: Result<number>[] = [
{ ok: false, error: "retry" },
{ ok: true, value: 12 },
];
console.log(values(attempts).join(","));