{ "data": { "question": { "questionId": "2749", "questionFrontendId": "2637", "categoryTitle": "JavaScript", "boundTopicId": 2222267, "title": "Promise Time Limit", "titleSlug": "promise-time-limit", "content": "

Given an asynchronous function fn and a time t in milliseconds, return a new time limited version of the input function. fn takes arguments provided to the time limited function.

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The time limited function should follow these rules:

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Example 1:

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\nInput: \nfn = async (n) => { \n  await new Promise(res => setTimeout(res, 100)); \n  return n * n; \n}\ninputs = [5]\nt = 50\nOutput: {"rejected":"Time Limit Exceeded","time":50}\nExplanation:\nconst limited = timeLimit(fn, t)\nconst start = performance.now()\nlet result;\ntry {\n   const res = await limited(...inputs)\n   result = {"resolved": res, "time": Math.floor(performance.now() - start)};\n} catch (err) {\n   result = {"rejected": err, "time": Math.floor(performance.now() - start)};\n}\nconsole.log(result) // Output\n\nThe provided function is set to resolve after 100ms. However, the time limit is set to 50ms. It rejects at t=50ms because the time limit was reached.\n
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Example 2:

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\nInput: \nfn = async (n) => { \n  await new Promise(res => setTimeout(res, 100)); \n  return n * n; \n}\ninputs = [5]\nt = 150\nOutput: {"resolved":25,"time":100}\nExplanation:\nThe function resolved 5 * 5 = 25 at t=100ms. The time limit is never reached.\n
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Example 3:

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\nInput: \nfn = async (a, b) => { \n  await new Promise(res => setTimeout(res, 120)); \n  return a + b; \n}\ninputs = [5,10]\nt = 150\nOutput: {"resolved":15,"time":120}\nExplanation:\n​​​​The function resolved 5 + 10 = 15 at t=120ms. The time limit is never reached.\n
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Example 4:

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\nInput: \nfn = async () => { \n  throw "Error";\n}\ninputs = []\nt = 1000\nOutput: {"rejected":"Error","time":0}\nExplanation:\nThe function immediately throws an error.
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Constraints:

\n\n\n", "translatedTitle": "有时间限制的 Promise 对象", "translatedContent": "

请你编写一个函数,它接受一个异步函数 fn 和一个以毫秒为单位的时间 t。它应根据限时函数返回一个有 限时 效果的函数。函数 fn 接受提供给 限时 函数的参数。

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限时 函数应遵循以下规则:

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示例 1:

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\n输入:\nfn = async (n) => { \n  await new Promise(res => setTimeout(res, 100)); \n  return n * n; \n}\ninputs = [5]\nt = 50\n输出:{\"rejected\":\"Time Limit Exceeded\",\"time\":50}\n解释:\nconst limited = timeLimit(fn, t)\nconst start = performance.now()\nlet result;\ntry {\n   const res = await limited(...inputs)\n   result = {\"resolved\": res, \"time\": Math.floor(performance.now() - start)};\n} catch (err) {\n   result = {\"rejected\": err, \"time\": Math.floor(performance.now() - start)};\n}\nconsole.log(result) // 输出结果\n\n提供的函数设置在 100ms 后执行完成,但是设置的超时时间为 50ms,所以在 t=50ms 时拒绝因为达到了超时时间。\n
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示例 2:

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\n输入:\nfn = async (n) => { \n  await new Promise(res => setTimeout(res, 100)); \n  return n * n; \n}\ninputs = [5]\nt = 150\n输出:{\"resolved\":25,\"time\":100}\n解释:\n在 t=100ms 时执行 5*5=25 ,没有达到超时时间。\n
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示例 3:

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\n输入:\nfn = async (a, b) => { \n  await new Promise(res => setTimeout(res, 120)); \n  return a + b; \n}\ninputs = [5,10]\nt = 150\n输出:{\"resolved\":15,\"time\":120}\n解释:\n在 t=120ms 时执行 5+10=15,没有达到超时时间。\n
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示例 4:

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\n输入:\nfn = async () => { \n  throw \"Error\";\n}\ninputs = []\nt = 1000\n输出:{\"rejected\":\"Error\",\"time\":0}\n解释:\n此函数始终丢出 Error
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提示:

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