{"id":80,"date":"2022-01-11T08:27:49","date_gmt":"2022-01-11T08:27:49","guid":{"rendered":"http:\/\/114.132.224.28\/?p=80"},"modified":"2022-01-11T08:27:49","modified_gmt":"2022-01-11T08:27:49","slug":"javascript-getter-setter-pyramid%e9%98%85%e8%af%bb%e7%ac%94%e8%ae%b0","status":"publish","type":"post","link":"http:\/\/localhost\/2022\/01\/11\/javascript-getter-setter-pyramid%e9%98%85%e8%af%bb%e7%ac%94%e8%ae%b0\/","title":{"rendered":"JAVASCRIPT GETTER-SETTER PYRAMID\u9605\u8bfb\u7b14\u8bb0"},"content":{"rendered":"\n

\u539f\u6587:<\/p>\n\n\n\n

https:\/\/staltz.com\/javascript-getter-setter-pyramid.html<\/a><\/p>\n\n\n\n

Functions<\/h4>\n\n\n\n
\"\"<\/figure>\n\n\n\n

\u4e0e\u786c\u7f16\u7801\u76f8\u6bd4\u3002\u51fd\u6570\u63d0\u4f9b\u4e00\u4e9b\u597d\u5904\uff1a<\/p>\n\n\n\n

  • \u60f0\u6027\/\u53ef\u590d\u7528<\/li><\/ul>\n\n\n\n

    \u5728\u51fd\u6570\u91cc\u7684\u4ee3\u7801\u662f\u60f0\u6027\u7684\uff08\u4ed6\u4e0d\u4f1a\u6267\u884c\u9664\u975e\u88ab\u8c03\u7528\uff09<\/p>\n\n\n\n

    • \u5b9e\u73b0\u7075\u6d3b<\/li><\/ul>\n\n\n\n

      \u51fd\u6570\u7684\u4f7f\u7528\u8005\u5e76\u4e0d\u5173\u5fc3\u51fd\u6570\u5185\u90e8\u662f\u5982\u4f55\u5b9e\u73b0\u7684\uff0c\u56e0\u6b64\u8fd9\u610f\u5473\u7740\u53ef\u4ee5\u7075\u6d3b\u5730\u4ee5\u5404\u79cd\u65b9\u5f0f\u5b9e\u73b0\u51fd\u6570\u3002<\/p>\n\n\n\n

      <\/p>\n\n\n\n

      Getter:<\/h4>\n\n\n\n
      \"\"<\/figure>\n\n\n\n

      () => X<\/strong><\/code><\/p>\n\n\n\n

      Getter\u6ca1\u6709\u8f93\u5165\u503c\uff0c\u5e76\u8fd4\u56de\u4e00\u4e2aX\u503c\u7684\u51fd\u6570<\/p>\n\n\n\n

      Getter\u662f\u4e00\u79cd\u4e0d\u9700\u8981\u53c2\u6570\u4f20\u9012\uff0c\u4f46\u662f\u4f1a\u8fd4\u56de\u4e00\u4e2a\u503c\u7684\u51fd\u6570\uff0c\u5728JavaScript\u4e2d\u6709\u5f88\u591agetter\uff0c\u6bd4\u5982Math.radom(),Date.now()\u7b49\u7b49\uff0cGetter \u4f5c\u4e3a\u503c\u7684\u62bd\u8c61\u4e5f\u5f88\u6709\u7528\u3002\u6bd4\u5982\uff1a<\/p>\n\n\n\n

      const<\/strong> user = {name: 'Alice', age: 30};\nconsole.log(user.name); \/\/ Alice<\/em>\n\n\nfunction<\/strong> getUser() {\n  return<\/strong> {name: 'Alice', age: 30};\n}\nconsole.log(getUser().name); \/\/ Alice<\/em><\/code><\/pre>\n\n\n\n
      \u901a\u8fc7\u4f7f\u7528 getter \u6765\u8868\u793a\u4e00\u4e2a\u503c\uff0c\u6211\u4eec\u7ee7\u627f\u4e86\u51fd\u6570\u7684\u597d\u5904\uff0c\u6bd4\u5982\u60f0\u6027\uff1a\u5982\u679c\u6211\u4eec\u4e0d\u8c03\u7528 getUser()\uff0c\u90a3\u4e48\u7528\u6237\u5bf9\u8c61\u5c31\u4e0d\u4f1a\u767d\u767d\u521b\u5efa\u3002<\/p>\n\n\n\n
      \u6211\u4eec\u4e5f\u5f97\u5230\u4e86\u5b9e\u73b0\u7075\u6d3b\u7684\u597d\u5904\uff0c\u56e0\u4e3a\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u591a\u79cd\u4e0d\u540c\u7684\u65b9\u5f0f\u8ba1\u7b97<\/strong>\u8fd4\u56de\u5bf9\u8c61\uff0c\u6216\u8005\u901a\u8fc7\u521b\u5efa\u4e00\u4e2a\u666e\u901a\u5bf9\u8c61\uff0c\u6216\u8005\u901a\u8fc7\u8fd4\u56de\u4e00\u4e2a\u7c7b\u7684\u5b9e\u4f8b\uff0c\u6216\u8005\u901a\u8fc7\u4f7f\u7528\u539f\u578b\u4e0a\u7684\u5c5e\u6027\u7b49\u3002\u4f7f\u7528\u786c\u7f16\u7801\u7684\u503c\uff0c\u6211\u4eec\u5c06\u6ca1\u6709\u8fd9\u79cd\u7075\u6d3b\u6027\u3002<\/p>\n\n\n\n
      Getter \u8fd8\u63d0\u4f9b\u4e86\u53ef\u4ee5\u6267\u884c\u526f\u4f5c\u7528\u7684hook\u3002\u6bcf\u5f53\u6267\u884c getter \u65f6\uff0c\u6211\u4eec\u90fd\u53ef\u4ee5\u89e6\u53d1\u6709\u7528\u7684\u526f\u4f5c\u7528\uff0c\u4f8b\u5982 console.log \u6216\u89e6\u53d1 Analytics \u4e8b\u4ef6\uff0c\u4f8b\u5982\uff1a<\/p>\n\n\n\n
      function<\/strong> getUser() {\n  Analytics.sendEvent('User object is now being accessed');\n  return<\/strong> {name: 'Alice', age: 30};\n}<\/code><\/pre>\n\n\n\n
      getter \u4e0a\u7684\u8ba1\u7b97\u4e5f\u53ef\u4ee5\u662f\u62bd\u8c61\u7684\uff0c\u56e0\u4e3a\u51fd\u6570\u53ef\u4ee5\u4f5c\u4e3a JavaScript \u4e2d\u7684\u4e00\u7b49\u503c\u4f20\u9012\u3002\u4f8b\u5982\uff0c\u8003\u8651\u8fd9\u4e2a\u4ee5 getter \u4f5c\u4e3a\u53c2\u6570\u7684\u52a0\u6cd5\u51fd\u6570\uff0c\u5e76\u8fd4\u56de\u4e00\u4e2a\u6570\u5b57\u7684 getter\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u8fd4\u56de\u4e00\u4e2a\u6570\u5b57\u3002<\/p>\n\n\n\n
      function<\/strong> add(getX, getY) {\n  return<\/strong> function<\/strong> getZ() {\n    const<\/strong> x = getX();\n    const<\/strong> y = getY();\n    return<\/strong> x + y;\n  }\n}<\/code><\/pre>\n\n\n\n
      \u5f53 getter \u8fd4\u56de\u4e0d\u53ef\u9884\u6d4b\u7684\u503c\u65f6\uff0c\u8fd9\u79cd\u62bd\u8c61\u8ba1\u7b97\u7684\u597d\u5904\u66f4\u52a0\u660e\u663e\uff0c\u4f8b\u5982\u4f7f\u7528 getter Math.random\uff1a<\/p>\n\n\n\n
      const<\/strong> getTen = () => 10;\nconst<\/strong> getTenPlusRandom = add(getTen, Math.random);\n\nconsole.log(getTenPlusRandom()); \/\/ 10.948117215055046<\/em>\nconsole.log(getTenPlusRandom()); \/\/ 10.796721274448556<\/em>\nconsole.log(getTenPlusRandom()); \/\/ 10.15350303918338<\/em>\nconsole.log(getTenPlusRandom()); \/\/ 10.829703269933633<\/em><\/code><\/pre>\n\n\n\n
      getter \u4e0e Promises \u4e00\u8d77\u4f7f\u7528\u4e5f\u5f88\u5e38\u89c1\uff0c\u56e0\u4e3a\u5df2\u77e5 Promise \u4e0d\u662f\u53ef\u91cd\u7528\u7684\u8ba1\u7b97\uff0c\u56e0\u6b64\u5c06 Promise \u6784\u9020\u51fd\u6570\u5305\u88c5\u5728 getter\uff08\u4e5f\u79f0\u4e3a\u201c\u5de5\u5382\u201d\u6216\u201cthunk\u201d\uff09\u4e2d\u4f7f\u5176\u53ef\u91cd\u7528\u3002<\/p>\n\n\n\n
      const p = function() {\n  return new Promise(){}\n}<\/code><\/pre>\n\n\n\n
      GETTER GETTERS<\/h4>\n\n\n\n
      () => (() => X)<\/strong><\/code><\/p>\n\n\n\n
      getter-getter \u662f\u4e00\u4e2a\u6ca1\u6709\u8f93\u5165\u53c2\u6570\u548c\u8fd4\u56de\u4e00\u4e2a getter \u7684\u51fd\u6570\u3002<\/p>\n\n\n\n
      \"\"<\/figure>\n\n\n\n
      getter-getter\u7684\u51fa\u73b0\u662f\u4e3a\u4e86\u89e3\u51b3\u904d\u5386\u5e8f\u5217\u7684\u95ee\u9898\u3002\u4f8b\u5982\uff0c\u5982\u679c\u6211\u4eec\u60f3\u663e\u793a\u6570\u5b57\u5e8f\u5217\u662f 2 \u7684\u5e42\uff0c\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 getter getNextPowerOfTwo()<\/p>\n\n\n\n
      let<\/strong> i = 2;\nfunction<\/strong> getNextPowerOfTwo() {\n  const<\/strong> next = i;\n  i = i * 2;\n  return<\/strong> next;\n}\n\nconsole.log(getNextPowerOfTwo()); \/\/ 2<\/em>\nconsole.log(getNextPowerOfTwo()); \/\/ 4<\/em>\nconsole.log(getNextPowerOfTwo()); \/\/ 8<\/em>\nconsole.log(getNextPowerOfTwo()); \/\/ 16<\/em>\nconsole.log(getNextPowerOfTwo()); \/\/ 32<\/em>\nconsole.log(getNextPowerOfTwo()); \/\/ 64<\/em>\nconsole.log(getNextPowerOfTwo()); \/\/ 128<\/em><\/code><\/pre>\n\n\n\n
      \u4e0a\u9762\u4ee3\u7801\u7684\u95ee\u9898\u662f\u53d8\u91cf i \u662f\u5168\u5c40\u58f0\u660e\u7684\uff0c\u5982\u679c\u6211\u4eec\u60f3\u91cd\u65b0\u542f\u52a8\u5e8f\u5217\uff0c\u6211\u4eec\u5fc5\u987b\u4ee5\u6b63\u786e\u7684\u65b9\u5f0f\u64cd\u4f5c\u8fd9\u4e2a\u53d8\u91cf\uff0c\u6cc4\u9732 getter \u7684\u5b9e\u73b0\u7ec6\u8282\u3002<\/p>\n\n\n\n
      \u4e3a\u4e86\u4f7f\u4e0a\u9762\u7684\u4ee3\u7801\u53ef\u91cd\u7528\u5e76\u4e14\u6ca1\u6709\u5168\u5c40\u53d8\u91cf\uff0c\u9700\u8981\u505a\u7684\u662f\u5c06 getter \u5305\u88c5\u5728\u53e6\u4e00\u4e2a\u51fd\u6570\u4e2d\u3002\u800c\u4e14\u8fd9\u4e2a\u5305\u88c5\u51fd\u6570\u4e5f\u662f\u4e00\u4e2agetter\u3002<\/p>\n\n\n\n
      getter-getters\u4f1a\u7ee7\u627fgetter\u7684\u6240\u4ee5\u4f18\u70b9\u3002\u6bd4\u5982\uff1a\u4f8b\u5982\uff1a\uff081\uff09\u5b9e\u73b0\u7684\u7075\u6d3b\u6027\uff0c\uff082\uff09\u526f\u4f5c\u7528\u7684\u94a9\u5b50\uff0c\uff083\uff09\u60f0\u6027\u3002\u8fd9\u6b21\u7684\u60f0\u6027\u4f53\u73b0\u5728\u521d\u59cb\u5316\u6b65\u9aa4\u4e2d\u3002\u5916\u90e8\u51fd\u6570\u53ef\u4ee5\u5ef6\u8fdf\u53d8\u91cf\u521d\u59cb\u5316\uff0c\u800c\u5185\u90e8\u51fd\u6570\u53ef\u4ee5\u5ef6\u8fdf\u904d\u5386\u503c\u3002<\/p>\n\n\n\n
      function getGetNext() {\n  let i = 2;\n  return function getNext() {\n    const next = i;\n    i = i * 2;\n    return next;\n  }\n}\n\nlet getNext = getGetNext();\nconsole.log(getNext()); \/\/ 2\nconsole.log(getNext()); \/\/ 4\nconsole.log(getNext()); \/\/ 8\ngetNext = getGetNext(); \/\/ \ud83d\udd37 restart!\nconsole.log(getNext()); \/\/ 2\nconsole.log(getNext()); \/\/ 4\nconsole.log(getNext()); \/\/ 8\nconsole.log(getNext()); \/\/ 16\nconsole.log(getNext()); \/\/ 32<\/code><\/pre>\n\n\n\n
      Iterables<\/h4>\n\n\n\n
      () => (() => ({done, value}))<\/code><\/p>\n\n\n\n
      \u53ef\u8fed\u4ee3\u51fd\u6570\u662f\u7279\u6b8a\u5316\u7684getter-getter\uff0c\u8fd4\u56de\u4e00\u4e2a\u5bf9\u8c61\u5f62\u5f0f\u5305\u542bvalue\u548cdone\u7684x\u503c\u3002<\/p>\n\n\n\n
      \"\"<\/figure>\n\n\n\n
      getter-getter \u80fd\u591f\u8868\u793a\u53ef\u91cd\u65b0\u542f\u52a8\u7684\u503c\u5e8f\u5217\uff0c\u4f46\u5b83\u4eec\u6ca1\u6709\u7ea6\u5b9a\u6765\u8868\u793a\u5e8f\u5217\u7684\u7ed3\u675f\u3002<\/p>\n\n\n\n
      \u8fd4\u56de\u7684\u8fed\u4ee3\u5bf9\u8c61\u7684done\u503c\uff0c\u53ef\u4ee5\u8ba9\u5916\u90e8\u77e5\u9053\u4f55\u65f6\u7ec8\u6b62\u8fed\u4ee3\u3002<\/p>\n\n\n\n
      function<\/strong> getGetNext() {\n  let<\/strong> i = 40;\n  return<\/strong> function<\/strong> getNext() {\n    if<\/strong> (i <= 48) {\n      const<\/strong> next = i;\n      i += 2;\n      return<\/strong> {done: false<\/strong>, value: next};\n    } else<\/strong> {\n      return<\/strong> {done: true<\/strong>};\n    }\n  }\n}\n\nlet<\/strong> getNext = getGetNext();\nfor<\/strong> (let<\/strong> result = getNext(); !result.done; result = getNext()) {\n  console.log(result.value);\n}<\/code><\/pre>\n\n\n\n
      ES6 \u7684\u8fed\u4ee3\u5668\u8fd8\u6709\u8fdb\u4e00\u6b65\u7ea6\u5b9a\u8fd9\u4e2agetter-getters\u7684\u5b9e\u73b0\uff0c\u4ed6\u4eec\u4f1a\u52a0\u4e00\u4e2a\u5305\u88c5\u5bf9\u8c61\u7ed9\u6bcf\u4e00\u4e2agetter<\/p>\n\n\n\n
      • \u5916\u90e8 getter f \u4f1a\u53d8\u6210\u4e00\u4e2a\u5bf9\u8c61 { [Symbol.iteration]: f }<\/li>
      • \u5185\u90e8 getter g \u4f1a\u53d8\u6210\u4e00\u4e2a\u5bf9\u8c61{ next: g }<\/li><\/ul>\n\n\n\n
        \u8fd9\u662f\u4e0a\u8ff0\u4f8b\u5b50\u7b26\u5408es6\u89c4\u8303\u7684\u4ee3\u7801:<\/p>\n\n\n\n
        const oddNums= {\n  [Symbol.iterator]: () => {\n    let i = 40;\n    return {\n     next: () => {\n       if (i <= 48) {\n          const next = i;\n          i += 2;\n          return {done: false, value: next};\n        } else {\n          return {done: true};\n        }\n     }\n   }\n  }\n}\n\nlet getOddNum = oddNums[Symbol.iterator]();\nfor (let result = getOddNum.next(); !result.done; result = getOddNum.next()) {\n  console.log(result.value);\n}<\/code><\/pre>\n\n\n\n
        \u4ee5\u8fd9\u79cd\u5f62\u5f0f\u5b9e\u73b0\u5c31\u80fd\u7528\u5230ES6 \u63d0\u4f9b\u8bed\u6cd5\u7cd6 for-let-of\u80fd\u66f4\u65b9\u4fbf\u5730\u4f7f\u7528 Iterables\uff1a(\u7701\u7565next\u8c03\u7528\u5e76\u5f53done\u4e3atrue\u7684\u65f6\u5019\u7ec8\u6b62\u5faa\u73af)<\/p>\n\n\n\n
        for<\/strong> (let<\/strong> x of<\/strong> oddNums) {\n  console.log(x);\n}<\/code><\/pre>\n\n\n\n
        \u4e3a\u4e86\u8f7b\u677e\u521b\u5efa Iterables\uff0cES6 \u8fd8\u63d0\u4f9b\u4e86\u751f\u6210\u8fed\u4ee3\u5bf9\u8c61\u51fd\u6570\u8bed\u6cd5\u7cd6\u51fd\u6570*\uff1a\uff08\u5373\u7701\u7565\u6389[Symbol.iterator]\u5bf9\u8c61\u51fd\u6570\u548creturn\u7684next\u5bf9\u8c61\u51fd\u6570\uff0c\u5e76\u7b80\u5316 return{ value: any, done: boolean}, \u76f4\u63a5yield\u540e\u9762\u662fvalue\uff0c\u7ed3\u675f\u8bed\u53e5return\u5373\u53ef\uff09<\/p>\n\n\n\n
        function<\/strong>* oddNums() {\n  let<\/strong> i = 40;\n  while<\/strong> (true<\/strong>) {\n    if<\/strong> (i <= 48) {\n      const<\/strong> value= i;\n      i += 2;\n      yield<\/strong> value;\n    } else<\/strong> {\n      return<\/strong>;\n    }\n  }\n}\n}\n\nfor (let x of oddNums()) {\n  console.log(x);\n}<\/code><\/pre>\n\n\n\n
        \u81eaes2015\uff0c\u6709\u4e86\u521b\u5efa\u8fed\u4ee3\u5bf9\u8c61\u7684\u8bed\u6cd5\u7cd6\u51fd\u6570function*\u548c\u8fed\u4ee3\u8fed\u4ee3\u5bf9\u8c61\u7684\u8bed\u6cd5\u7cd6for…of\u5c31\u53d8\u5f97\u66f4\u65b9\u4fbf\u7684\u521b\u5efa\u8fed\u4ee3\u3002<\/p>\n\n\n\n
        const oddNums= {\n  [Symbol.iterator](){\n    let i = 40;\n    let outside, error\n    return {\n     next(outside){\n      try{\n          if (i <= 48) {\n          const next = i ;\n          i += 2;\n          outside = outside\n          if(error) throw(error)\n          return {done: false, value: next};\n        } else {\n          return {done: true};\n        }\n      }catch(e){\n        console.log(e)\n      } \n     },\n     error(str){\n       error = str\n       this.next()\n    }\n   }\n  }\n}\n\nlet getOddNum = oddNums[Symbol.iterator]();\nfor (let result = getOddNum.next(); !result.done; result = getOddNum.next()) {\n  console.log(result.value);\n}<\/code><\/pre>\n\n\n\n
        Setters:<\/h4>\n\n\n\n
        \"\"<\/figure>\n\n\n\n
        X => ()<\/strong><\/code><\/p>\n\n\n\n
        setter \u662f\u4e00\u4e2a\u4ee5 X \u4f5c\u4e3a\u8f93\u5165\u4f46\u6ca1\u6709\u8f93\u51fa\u7684\u51fd\u6570<\/p>\n\n\n\n
        Setter \u662f\u4e00\u79cd\u51fd\u6570\uff0c\u63a5\u53d7\u53c2\u6570\uff0c\u4f46\u4e0d\u8fd4\u56de\u8f93\u51fa\u503c\u3002 JavaScript \u8fd0\u884c\u65f6\u548c DOM \u4e2d\u6709\u8bb8\u591a\u539f\u751f\u7684 setter\uff0c\u4f8b\u5982 console.log(x)\u3001document.write(x) \u7b49\u3002<\/p>\n\n\n\n
        \u4e0e getter \u4e0d\u540c\uff0csetter \u901a\u5e38\u4e0d\u662f\u62bd\u8c61\uff0c\u56e0\u4e3a\u5982\u679c\u51fd\u6570\u6ca1\u6709\u503c\uff0c\u5219\u610f\u5473\u7740\u8be5\u51fd\u6570\u4ec5\u7528\u4e8e\u53d1\u9001\u6570\u636e\u6216\u547d\u4ee4 JavaScript \u8fd0\u884c\u65f6\u3002<\/p>\n\n\n\n
        \u5bf9\u4e8e\u6211\u4eec\u7684\u4f8b\u5b50\uff0cgetTen\u662f\u4e00\u4e2a\u5bf9\u4e8e10\u7684\u62bd\u8c61\uff0c\u6211\u4eec\u53ef\u4ee5\u4f20\u9012getter\u4f5c\u4e3a\u4e00\u4e2a\u503c\uff0c\u4f46\u662f\u4f20\u4e00\u4e2asetTen\u662f\u6ca1\u6709\u610f\u4e49\u7684\uff0c\u56e0\u4e3a\u4f60\u4e0d\u4f1a\u4ece\u8c03\u7528\u51fd\u6570\u4e2d\u62ff\u5230\u4ec0\u4e48\u503c\u3002<\/p>\n\n\n\n
        \u8fd9\u5c31\u662f\u8bf4setters\u53ef\u4ee5\u662f\u5176\u4ed6 setter \u7684\u7b80\u5355\u5305\u88c5\u5668\u3002\u8003\u8651 console.log \u8bbe\u7f6e\u5668\u7684\u8fd9\u4e2a\u5305\u88c5\u5668\uff1a<\/p>\n\n\n\n
        function<\/strong> fancyConsoleLog(str) {\n  console.log('\u2b50 ' + str + ' \u2b50');\n}\n<\/code><\/pre>\n\n\n\n
        Setter Setters<\/p>\n\n\n\n
        (X => ()) => ()<\/strong><\/code><\/p>\n\n\n\n
        setter-setter \u662f\u4e00\u4e2a\u4ee5 setter \u4f5c\u4e3a\u8f93\u5165\u4f46\u6ca1\u6709\u8f93\u51fa\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n
        \"\"<\/figure>\n\n\n\n
        \u867d\u7136\u57fa\u672c\u7684 setter \u4e0d\u662f\u62bd\u8c61\u51fd\u6570\uff08console.log\uff09\uff0c\u4f46 setter-setter \u80fd\u5728\u4ee3\u7801\u5e93\u5f53\u4e2d\u4f5c\u4e3a\u5982\u4f55\u5229\u7528\u5448\u73b0\u8fd9\u4e2a\u503c\u7684\u62bd\u8c61\u51fd\u6570(fn(cb){cb(val)})\u3002<\/p>\n\n\n\n
        \u4f8b\u5982\uff0c\u8003\u8651\u5982\u4f55\u901a\u8fc7\u8fd9\u4e2a setter-setter \u6765\u8868\u793a\u6570\u5b57 10\uff1a<\/p>\n\n\n\n
        function<\/strong> setSetTen(setTen) {\n  setTen(10)\n}\n<\/code><\/pre>\n\n\n\n
        \u6ce8\u610f\u8fd9\u91cc\u6ca1\u6709\u8fd4\u56de\u503c\uff0c\u56e0\u4e3asetter\u6c38\u8fdc\u4e0d\u4f1a\u8fd4\u56de\u503c\u3002\u901a\u8fc7\u7b80\u5355\u5730\u91cd\u547d\u540d\u4e00\u4e9b\u53c2\u6570\uff0c\u4e0a\u9762\u7684\u793a\u4f8b\u53ef\u80fd\u66f4\u5177\u53ef\u8bfb\u6027\uff1a<\/p>\n\n\n\n
        function<\/strong> setTenListener(cb) {\n  cb(10)\n}<\/code><\/pre>\n\n\n\n
        \u987e\u540d\u601d\u4e49\uff0ccb \u4ee3\u8868\u201c\u56de\u8c03\u201d\uff0c\u5e76\u8bf4\u660e\u4e86 setter-setter \u5728 JavaScript \u4e2d\u662f\u5982\u4f55\u5e38\u89c1\u7684\uff0c\u56e0\u4e3a\u6709\u5927\u91cf\u7684\u56de\u8c03\u7528\u4f8b\u3002<\/p>\n\n\n\n
        \u8c03\u7528\u4e00\u4e2asetter-setter\u7684\u62bd\u8c61\u51fd\u6570\uff0c\u4ed6\u7684\u76f8\u53cd\u65b9\u6cd5\u662f\u8c03\u7528\u4e00\u4e2agetter<\/p>\n\n\n\n
        setter(setter)<\/p>\n\n\n\n
        setter(getter())<\/p>\n\n\n\n
        \u4e0b\u9762\u7684\u8fd9\u4e24\u4e2a\u793a\u4f8b\u5728\u529f\u80fd\u4e0a\u662f\u7b49\u6548\u7684\uff0c\u4f46\u8c03\u7528\u65b9\u5f0f\u5374\u5927\u4e0d\u76f8\u540c\u3002<\/p>\n\n\n\n
        setSetTen(console.log);\n\n\/\/ compare with...\n\nconsole.log(getTen());\n<\/code><\/pre>\n\n\n\n
        setter-setter \u7684\u597d\u5904\u4e0e getter \u76f8\u540c\u2014\u2014\u60f0\u6027\u3001\u5b9e\u73b0\u7075\u6d3b\u6027\u3001\u526f\u4f5c\u7528\u6302\u94a9\u2014\u2014\u4f46\u6709\u4e24\u4e2a getter \u6ca1\u6709\u7684\u65b0\u5c5e\u6027\uff1a\u63a7\u5236\u53cd\u8f6c\uff08\u51fd\u6570\u91cc\u9762\u51b3\u5b9a\u5982\u4f55\u8c03\u7528\u90a3\u4e2a\u4f20\u8fdb\u6765\u7684\u51fd\u6570,setter\u4f5c\u4e3a\u53c2\u6570\u4f20\u8fdb\u6765\uff0c\u518dsetter\u91cc\u9762\u518d\u8c03\u7528\uff09\u548c\u5f02\u6b65\u6027\u3002\u800cgetter\u5c31\u9700\u8981\u5148\u8c03\u7528\u8f6c\u5316\u4e3a\u503c\u4e4b\u540e\u518d\u4f20\u7ed9setter\u3002<\/p>\n\n\n\n
        \u4e0a\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u4f7f\u7528 getter \u7684\u4ee3\u7801\u6307\u793a getter \u4f55\u65f6\u4e0e console.log \u4e00\u8d77\u4f7f\u7528\u3002\u4f46\u662f\uff0c\u5f53\u4f7f\u7528 setter-setter \u65f6\uff0c\u662f setter-setter \u672c\u8eab\u51b3\u5b9a\u4f55\u65f6\u8c03\u7528 console.log\u3002\u8fd9\u79cd\u63a7\u5236\u53cd\u8f6c\u5141\u8bb8 setter-setter \u6bd4 getter \u62e5\u6709\u66f4\u591a\u7684\u6743\u529b\uff0c\u4f8b\u5982\u901a\u8fc7\u5411setter\u5185\u90e8\u53d1\u9001\u8bb8\u591a\u503c\u7ed9\u4f20\u9012\u8fdb\u6765\u7684setter\uff1a<\/p>\n\n\n\n
        function<\/strong> setSetTen(setTen) {\n  setTen(10)\n  setTen(10)\n  setTen(10)\n  setTen(10)\n}<\/code><\/pre>\n\n\n\n
        \u63a7\u5236\u53cd\u8f6c\u8fd8\u5141\u8bb8 setter-setter \u51b3\u5b9a\u4f55\u65f6\u5411\u56de\u8c03\u4f20\u9012\u503c\uff0c\u4f8b\u5982\u5f02\u6b65\u4f20\u9012\u3002\u56de\u60f3\u4e00\u4e0b setSetTen \u7684\u53e6\u4e00\u4e2a\u540d\u79f0\u53ef\u80fd\u662f setTenListener\uff1a<\/p>\n\n\n\n
        function<\/strong> setTenListener(cb) {\n  setTimeout(() => { cb(10); }, 1000);\n}<\/code><\/pre>\n\n\n\n
        <\/p>\n\n\n\n
        Promise<\/h4>\n\n\n\n
        \"\"<\/figure>\n\n\n\n
        (X => (), Err => ()) => ()<\/code><\/p>\n\n\n\n
        Promise\u662f\u63a5\u53d7\u4e24\u4e2asetter\u7684setter-setter\u51fd\u6570\uff0c\u5e76\u6709\u4e00\u4e9b\u989d\u5916\u4fdd\u8bc1\u3002<\/p>\n\n\n\n
        \u867d\u7136 setter-setter \u529f\u80fd\u5f3a\u5927\uff0c\u4f46\u7531\u4e8e\u63a7\u5236\u53cd\u8f6c\uff0c\u5b83\u4eec\u53ef\u80fd\u975e\u5e38\u4e0d\u53ef\u9884\u6d4b\u3002\u5b83\u4eec\u53ef\u4ee5\u662f\u540c\u6b65\u7684\u6216\u5f02\u6b65\u7684\uff0c\u5e76\u4e14\u53ef\u4ee5\u968f\u65f6\u95f4\u4f20\u9012\u96f6\u4e2a\u6216\u4e00\u4e2a\u6216\u591a\u4e2a\u503c\u3002<\/p>\n\n\n\n
        Promise \u662f\u4e00\u79cd\u7279\u6b8a\u7684 setter-setter\uff0c\u5b83\u4e3a\u503c\u7684\u4f20\u9012\u63d0\u4f9b\u4e00\u4e9b\u4fdd\u8bc1\u3002<\/p>\n\n\n\n
        • \u5185\u90e8setter\u4e0d\u4f1a\u540c\u6b65\u8c03\u7528\u3002<\/li><\/ul>\n\n\n\n
          • \u5185\u90e8setter\u53ea\u4f1a\u8c03\u7528\u4e00\u6b21\u3002<\/li><\/ul>\n\n\n\n
            • \u63d0\u4f9b\u4e00\u4e2a\u53ef\u9009\u7684\u7b2c\u4e8c\u4e2asetter\u6765\u4f20\u9012\u9519\u8bef\u4fe1\u606f<\/li><\/ul>\n\n\n\n
              \u5bf9\u6bd4\uff1a<\/p>\n\n\n\n
              function setSetTen(setTen) {\n  setTen(10)\n  setTen(10)\n}\n\nconsole.log('before setSetTen');\nsetSetTen(console.log);\nconsole.log('after setSetTen');\n\/ (Log shows:)\n\/\/ before setSetTen\n\/\/ 10\n\/\/ 10\n\/\/ after setSetTen\n\nconst tenPromise = new Promise(function setSetTen(setTen) {\n  setTen(10);\n  setTen(10);\n});\n\nconsole.log('before Promise.then');\ntenPromise.then(console.log);\nconsole.log('after Promise.then');\n\n\/\/ (Log shows:)\n\/\/ before Promise.then\n\/\/ after Promise.then\n\/\/ 10<\/code><\/pre>\n\n\n\n
              Promise\u80fd\u5f88\u65b9\u4fbf\u7684\u8868\u793a\u4e00\u4e2a\u5f02\u6b65\u7684\u4e0d\u548c\u91cd\u7528\u503c\u7684\u51fd\u6570\uff0ces2017\u63d0\u4f9b\u80fd\u751f\u6210Promise\u548c\u4f7f\u7528promise\u7684\u8bed\u6cd5\u7cd6\uff0casync-await,async\u4f1a\u8fd4\u56de\u4e00\u4e2a\u7531Promise\u5305\u88f9\u7684\u503c,\u800cawait\u80fd\u89e3\u5f00Promise\u7684\u503c<\/p>\n\n\n\n
              async<\/strong> function<\/strong> getTenPromise() {\n  return<\/strong> 10;\n}\nconst<\/strong> tenPromise = getTenPromise();\n\nconsole.log('before Promise.then');\ntenPromise.then(console.log);\nconsole.log('after Promise.then');\n\n\/\/ (Log shows:)<\/em>\n\/\/ before Promise.then<\/em>\n\/\/ after Promise.then<\/em>\n\/\/ 10<\/em>\n\nasync function main() {\n  console.log('before await');\n  const ten = await new Promise(function setSetTen(setTen) {\n    setTen(10);\n  });\n  console.log(ten);\n  console.log('after await');\n}\n\nmain();\n\n\/\/ (Log shows:)\n\/\/ before await\n\/\/ 10\n\/\/ after await\n\n<\/code><\/pre>\n\n\n\n
              OBSERVABLES<\/h2>\n\n\n\n
              Observables<\/h4>\n\n\n\n
              \"\"<\/figure>\n\n\n\n
              (X => (), Err => (), () => ()) => ()<\/code><\/p>\n\n\n\n
              Observable\u662f\u63a5\u53d7\u4e09\u4e2asetter\u7684setter-setter\u51fd\u6570\uff0c\u5e76\u6709\u4e00\u4e9b\u989d\u5916\u7684\u4fdd\u8bc1\u3002<\/p>\n\n\n\n
              \u5c31\u50cf Iterables \u662f\u4e00\u79cd\u7279\u6b8a\u7c7b\u578b\u7684 getter-getter \u589e\u52a0\u4e86\u7ed3\u675f\u7684\u6807\u5fd7\uff0cObservables \u4e5f\u662f\u4e00\u79cd\u589e\u52a0\u4e86\u7528\u6765\u7ed3\u675f\u7684 setter-setter\u3002JavaScript \u4e2d\u5178\u578b\u7684 setter-setter\uff0c\u5982 element.addEventListener\uff0c\u4e0d\u901a\u77e5\u4e8b\u4ef6\u6d41\u662f\u5426\u5b8c\u6210\uff0c\u56e0\u6b64\u8fd9\u4f7f\u5f97\u8fde\u63a5\u4e8b\u4ef6\u6d41\u6216\u6267\u884c\u5176\u4ed6\u4e0e\u5b8c\u6210\u76f8\u5173\u7684\u903b\u8f91\u53d8\u5f97\u56f0\u96be\u3002<\/p>\n\n\n\n
              \u4e0d\u50cfIterables\uff0c\u6709\u6807\u51c6\u5316\u7684js\u5b9a\u4e49\uff0cObservables\u5728TC39\u6709\u8fc7\u63d0\u8bae\uff0c\u4f46\u8fd8\u6ca1\u88ab\u63a5\u53d7\u3002<\/p>\n\n\n\n
              Observables \u662f Iterables \u7684\u5bf9\u5076\uff0c\u8fd9\u53ef\u4ee5\u901a\u8fc7\u4e00\u4e9b\u5bf9\u79f0\u6027\u770b\u51fa<\/p>\n\n\n\n
              • Iterable<\/strong>
                • \u662f\u5bf9\u8c61<\/li>
                • \u6709\u201citerate\u201d \u65b9\u6cd5, a.k.a. Symbol.iterator<\/code><\/li>
                • \u201citerate\u201d \u65b9\u6cd5\u662f\u4e00\u4e2aIterator\u5bf9\u8c61\u91cc\u7684\u4e00\u4e2agetter\u65b9\u6cd5<\/li>
                • \u8fd4\u56de\u7684Iterator \u5bf9\u8c61\u4f1a\u6709\u4e00\u4e2anext\u65b9\u6cd5\u7684getter<\/li><\/ul><\/li>
                • Observable<\/strong>
                  • \u662f\u5bf9\u8c61<\/li>
                  • \u6709\u201cobserve\u201d \u65b9\u6cd5, a.k.a. subscribe<\/code><\/li>
                  • \u201cobserve\u201d \u65b9\u6cd5\u662f\u4e00\u4e2aObserver \u5bf9\u8c61\u91cc\u7684\u4e00\u4e2asetter\u65b9\u6cd5<\/li>
                  • \u8fd4\u56de\u7684Observer\u5bf9\u8c61\u4f1a\u6709\u4e00\u4e2anext\u65b9\u6cd5\u7684setter<\/li><\/ul><\/li><\/ul>\n\n\n\n
                    function setter-setter<\/p>\n\n\n\n
                    function setSetTen(next, err, complete) {\n   let x = 40;\n    let clock = setInterval(() => {\n      if (x <= 48) {\n        next(x);\n        x += 2;\n      } else {\n        complete();\n        clearInterval(clock);\n      }\n    }, 1000);\n\n   return function() {\n     clearInterval(clock)\n   }\n}<\/code><\/pre>\n\n\n\n
                    \u5c06\u4f20\u8fdb\u6765\u7684\u4e09\u4e2a\u51fd\u6570\u8f6c\u5316\u4e3aobserve\u5bf9\u8c61\uff1a<\/p>\n\n\n\n
                    const<\/strong> oddNums = {\n  subscribe: (observer) => {\n    let<\/strong> x = 40;\n    let<\/strong> clock = setInterval(() => {\n      if<\/strong> (x <= 48) {\n        observer.next(x);\n        x += 2;\n      } else<\/strong> {\n        observer.complete();\n        clearInterval(clock);\n      }\n    }, 1000);\n  }\n};\n\noddNums.subscribe({\n  next: x => console.log(x),\n  complete: () => console.log('done'),\n});<\/code><\/pre>\n\n\n\n
                    \u4e0e setter-setter \u4e00\u6837\uff0cObservables \u4f1a\u5bfc\u81f4\u63a7\u5236\u53cd\u8f6c\uff0c\u56e0\u6b64\u8c03\u7528\u4ee3\u7801\uff08oddNums.subscribe\uff09\u65e0\u6cd5\u6682\u505c\u6216\u53d6\u6d88\u4f20\u5165\u7684\u6570\u636e\u6d41\u3002<\/p>\n\n\n\n
                    \u5927\u591a\u6570 Observable \u5b9e\u73b0\u6dfb\u52a0\u4e86\u4e00\u4e2a\u91cd\u8981\u7684\u7ec6\u8282\uff0c\u4ee5\u5141\u8bb8\u4ece\u6d88\u8d39\u8005\u5230\u751f\u4ea7\u8005\u7684\u53d6\u6d88\u4f20\u8f93\u8ba2\u9605\u3002<\/p>\n\n\n\n
                      subscribe: (observer) => {\n    let<\/strong> x = 40;\n    let<\/strong> clock = setInterval(() => {\n      if<\/strong> (x <= 48) {\n        observer.next(x);\n        x += 2;\n      } else<\/strong> {\n        observer.complete();\n        clearInterval(clock);\n      }\n    }, 1000);\n    \/\/ \ud83d\udd37 Subscription:<\/em>\n    return<\/strong> {\n      unsubscribe: () => {\n        clearInterval(clock);\n      }\n    };\n  }\n};\n\nconst<\/strong> subscription = oddNums.subscribe({\n  next: x => console.log(x),\n  complete: () => console.log('done'),\n});\n\n\/\/ \ud83d\udd37 Cancel the incoming flow of data after 2.5 seconds<\/em>\nsetTimeout(() => {\n  subscription.unsubscribe();\n}, 2500);<\/code><\/pre>\n\n\n\n
                    <\/p>\n\n\n\n
                    Async Iterables<\/h4>\n\n\n\n
                    \"\"<\/figure>\n\n\n\n
                    () => (() => Promise<{done, value}>)<\/code><\/p>\n\n\n\n
                    \u5f02\u6b65\u8fed\u4ee3\u51fd\u6570\u5c31\u50cf\u4e00\u4e2ayield promise\u7684\u8fed\u4ee3\u3002<\/p>\n\n\n\n
                    Iterables \u53ef\u4ee5\u8868\u793a\u4efb\u4f55\u65e0\u9650\u6216\u6709\u9650\u7684\u503c\u5e8f\u5217\uff0c\u4f46\u5b83\u4eec\u6709\u4e00\u4e2a\u9650\u5236\uff1a\u4e00\u65e6\u6d88\u8d39\u8005\u8c03\u7528 next() \u65b9\u6cd5\uff0c\u8be5\u503c\u5fc5\u987b\u540c\u6b65\u53ef\u7528\u3002AsyncIterables \u901a\u8fc7\u5141\u8bb8\u201c\u7a0d\u540e\u201d\u800c\u4e0d\u662f\u5728\u8bf7\u6c42\u65f6\u7acb\u5373\u4f20\u9012\u503c\u6765\u6269\u5c55 Iterables \u7684\u529f\u80fd\u3002<\/p>\n\n\n\n
                    AsyncIterables \u4f7f\u7528 Promise \u5b9e\u73b0\u503c\u7684\u5f02\u6b65\u4f20\u9012\uff0c\u56e0\u4e3a Promise \u4ee3\u8868\u5355\u4e2a\u5f02\u6b65\u503c\u3002\u53ef\u4ee5\u901a\u8fc7\u8c03\u7528\u8fd9\u4e2aPromise\u540e\u5728value\u4f20\u9012\uff08yield\u5c31\u53ef\u4ee5\u4f20\u9012\u8fd9\u4e2a\uff09\u3002<\/p>\n\n\n\n
                    \u5728\u4e0b\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u91c7\u7528oddNums Iterable \u793a\u4f8b\u5e76\u4f7f\u5176\u4ea7\u751f\u5ef6\u8fdf\u540e\u89e3\u6790\u7684\u503c\u7684Promises\uff1a<\/p>\n\n\n\n
                    function slowResolve(val) {\n  return new Promise(resolve => {\n    setTimeout(() => resolve(val), 1000);\n  });\n}\n\nfunction* oddNums() {\n  let i = 40;\nfunction slowResolve(val) {\n  return new Promise(resolve => {\n    setTimeout(() => resolve(val), 1000);\n  });\n}\n\nfunction* oddNums() {\n  let i = 40;\n  while (true) {\n    if (i <= 48) {\n      yield slowResolve(i); \/\/ \ud83d\udd37 yield a Promise\n      i += 2;\n    } else {\n      return;\n    }\n  }\n}<\/code><\/pre>\n\n\n\n
                    \u8981\u4f7f\u7528 AsyncIterable\uff0c\u6211\u4eec\u53ef\u4ee5\u5728\u8bf7\u6c42\u4e0b\u4e00\u4e2a Promise \u4e4b\u524d\u7b49\u5f85\u6bcf\u4e2a\u4ea7\u751f\u7684 Promise\uff1a<\/p>\n\n\n\n
                    async<\/strong> function<\/strong> main() {\n  for<\/strong> (let<\/strong> promise of<\/strong> oddNums()) {\n    const<\/strong> x = await<\/strong> promise;\n    console.log(x);\n  }\n  console.log('done');\n}\n\nmain();\n\n\/\/ (Log shows:)<\/em>\n\/\/ 40<\/em>\n\/\/ 42<\/em>\n\/\/ 44<\/em>\n\/\/ 46<\/em>\n\/\/ 48<\/em>\n\/\/ done<\/em><\/code><\/pre>\n\n\n\n
                    \u4e0a\u9762\u7684\u793a\u4f8b\u4e3a AsyncIterables \u521b\u5efa\u4e86\u4e00\u4e2a\u5f88\u76f4\u89c2\uff0c\u4f46\u5b83\u5b9e\u9645\u4e0a\u4e0d\u662f\u4e00\u4e2a\u6709\u6548\u7684 ES2018 AsyncIterables\u3002\u6211\u4eec\u4e0a\u9762\u6240\u505a\u7684\u662f\u4e00\u4e2a ES6 Iterable of Promises\uff0c\u4f46 ES2018 AsyncIterables \u662f\u4e00\u4e2a {done, value} \u5bf9\u8c61\u7684 Promise \u7684 getter-getter\u3002\u6bd4\u8f83\u8fd9\u4e24\u4e2a\uff1a<\/p>\n\n\n\n
                    • Promise \u7684\u53ef\u8fed\u4ee3\uff1a () => (() => {done, value: Promise<X>}) <\/li>
                    • ES2018 AsyncIterable: () => (() => Promise<{done, value}>)<\/li><\/ul>\n\n\n\n
                      \u8fd9\u662f\u56e0\u4e3a\u9700\u8981\u5141\u8bb8\u8fd4\u56de\u7684done\u4e5f\u53ef\u80fd\u662f\u5f02\u6b65\u7684\uff0c\u6240\u4ee5\u662f\u7528Promise\u53bb\u8fd4\u56de\u6574\u4e2a{done, value}\u3002<\/p>\n\n\n\n
                      \u56e0\u4e3aAsyncIterable\u4e0d\u662f\u6709\u6548\u7684Iterable\uff0c\u6240\u4ee5\u662f\u7528\u53e6\u4e00\u4e2aSymbol\u5b9e\u73b0[Symbol.asyncIterator]<\/p>\n\n\n\n
                      const<\/strong> oddNums = {\n  [Symbol.asyncIterator]: () => {\n    let<\/strong> i = 40;\n    return<\/strong> {\n      next: () => {\n        if<\/strong> (i <= 48) {\n          const<\/strong> next = i;\n          i += 2;\n          return<\/strong> slowResolve({done: false<\/strong>, value: next});\n        } else<\/strong> {\n          return<\/strong> slowResolve({done: true<\/strong>});\n        }\n      }\n    };\n  }\n};\n\nasync<\/strong> function<\/strong> main() {\n  let<\/strong> iter = oddNums[Symbol.asyncIterator]();\n  let<\/strong> done = false<\/strong>;\n  for<\/strong> (let<\/strong> promise = iter.next(); !done; promise = iter.next()) {\n    const<\/strong> result = await<\/strong> promise;\n    done = result.done;\n    if<\/strong> (!done) console.log(result.value);\n  }\n  console.log('done');\n}\n\nmain();<\/code><\/pre>\n\n\n\n
                      \u8ddf\u666e\u901aIterable\u4e00\u6837\uff0c\u4e5f\u6709\u751f\u4ea7\u7aef\u548c\u6d88\u8d39\u7aef\u7684\u8bed\u6cd5\u7cd6<\/p>\n\n\n\n
                      function* -> async function *<\/p>\n\n\n\n
                      for..of -> await for..of<\/p>\n\n\n\n
                      function<\/strong> sleep(period) {\n  return<\/strong> new<\/strong> Promise(resolve => {\n    setTimeout(() => resolve(true<\/strong>), period);\n  });\n}\n\n\/\/ \ud83d\udd37 Production side can use both `await` and `yield`<\/em>\nasync<\/strong> function<\/strong>* oddNums() {\n  let<\/strong> i = 40;\n  while<\/strong> (true<\/strong>) {\n    if<\/strong> (i <= 48) {\n      await<\/strong> sleep(1000);\n      yield<\/strong> i;\n      i += 2;\n    } else<\/strong> {\n      await<\/strong> sleep(1000);\n      return<\/strong>;\n    }\n  }\n}\n\nasync<\/strong> function<\/strong> main() {\n  \/\/ \ud83d\udd37 Consumption side uses the new syntax `for await`<\/em>\n  for<\/strong> await<\/strong> (let<\/strong> x of<\/strong> oddNums()) {\n    console.log(x);\n  }\n  console.log('done');\n}\n\nmain();<\/code><\/pre>\n\n\n\n
                      \u8fd9\u5bf9\u4e8e\u8fed\u4ee3fetch\u53d1\u9001\u8bf7\u6c42\u5c31\u975e\u5e38\u65b9\u4fbf\u4e86<\/p>\n\n\n\n
                      async<\/strong> function<\/strong>* users(from<\/strong>, to) {\n  for<\/strong> (let<\/strong> x = from<\/strong>; x <= to; x++) {\n    const<\/strong> res = await<\/strong> fetch('http:\/\/jsonplaceholder.typicode.com\/users\/' + x);\n    const<\/strong> json = await<\/strong> res.json();\n    yield<\/strong> json;\n  }\n}\n\nasync<\/strong> function<\/strong> main() {\n  for<\/strong> await<\/strong> (let<\/strong> x of<\/strong> users(1, 10)) {\n    console.log(x);\n  }\n}\n\nmain();<\/code><\/pre>\n\n\n\n
                      Operators<\/h4>\n\n\n\n
                      Function\u4e5f\u53ef\u4ee5\u50cf\u503c\u4e00\u6837\u4f20\u9012\u7ed9\u51fd\u6570\uff0c\u65e0\u8bba\u662f\u4e0a\u9762\u7684Observables or AsyncIterables\uff0c\u6240\u4ee5\u6211\u4eec\u4e5f\u80fd\u5728\u522b\u7684\u51fd\u6570\u91cc\u64cd\u7eb5\u4ed6\u4eec\u6765\u5b9e\u73b0\u529f\u80fd\u3002<\/p>\n\n\n\n
                      \u6700\u5e38\u89c1\u7684\u64cd\u4f5c\u4e4b\u4e00\u662f map\uff0c\u5b83\u5728\u6570\u7ec4\u4e2d\u5f88\u6d41\u884c\uff0c\u4f46\u4e5f\u4e0e\u5176\u4ed6\u62bd\u8c61\u76f8\u5173\u3002\u5728\u4e0b\u9762\u7684\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u4e3a AsyncIterables \u521b\u5efa\u4e86 map \u8fd0\u7b97\u7b26\uff0c\u5e76\u4f7f\u7528\u5b83\u6765\u521b\u5efa\u6570\u636e\u5e93\u4e2d\u7528\u6237\u540d\u7684 AsyncIterable\u3002<\/p>\n\n\n\n
                      async<\/strong> function<\/strong>* users(from<\/strong>, to) {\n  for<\/strong> (let<\/strong> i = from<\/strong>; i <= to; i++) {\n    const<\/strong> res = await<\/strong> fetch('http:\/\/jsonplaceholder.typicode.com\/users\/' + i);\n    const<\/strong> json = await<\/strong> res.json();\n    yield<\/strong> json;\n  }\n}\n\n\/\/ \ud83d\udd37 Map operator for AsyncIterables<\/em>\nasync<\/strong> function<\/strong>* map(inputAsyncIter, f) {\n  for<\/strong> await<\/strong> (let<\/strong> x of<\/strong> inputAsyncIter) {\n    yield<\/strong> f(x);\n  }\n}\n\nasync<\/strong> function<\/strong> main() {\n  const<\/strong> allUsers = users(1, 10);\n  \/\/ \ud83d\udd37 Pass `allUsers` around, create a new AsyncIterable `names`<\/em>\n  const<\/strong> names = map(allUsers, user => user.name);\n  for<\/strong> await<\/strong> (let<\/strong> name of<\/strong> names) {\n    console.log(name);\n  }\n}\n\nmain();<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
                      \u539f\u6587: https:\/\/staltz.com\/ja …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/localhost\/wp-json\/wp\/v2\/posts\/80"}],"collection":[{"href":"http:\/\/localhost\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/localhost\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/localhost\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/localhost\/wp-json\/wp\/v2\/comments?post=80"}],"version-history":[{"count":0,"href":"http:\/\/localhost\/wp-json\/wp\/v2\/posts\/80\/revisions"}],"wp:attachment":[{"href":"http:\/\/localhost\/wp-json\/wp\/v2\/media?parent=80"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/localhost\/wp-json\/wp\/v2\/categories?post=80"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/localhost\/wp-json\/wp\/v2\/tags?post=80"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}