typesript 实现async await 源码

const sleep = time => new Promise(resolve => setTimeout(() => resolve(), time))
async function aaa() {
  await sleep(100)
}
aaa()

//运行tsc

var __awaiter = function (thisArg, _arguments, P, generator) {
  return new Promise(function (resolve, reject) {
    function fulfilled(value) {
      try {
        step(generator.next(value));
      } catch (e) {
        reject(e);
      }
    }
    function rejected(value) {
      try {
        step(generator["throw"](value));
      } catch (e) {
        reject(e);
      }
    }
    function step(result) {
      result.done ? resolve(result.value) : new Promise(function (resolve) {
        resolve(result.value);
      }).then(fulfilled, rejected);
    }
    step((generator = generator.apply(thisArg, _arguments || [])).next());
  });
};
var __generator = function (thisArg, body) {
  var _ = {
    label: 0,
    sent: function () {
      if (t[0] & 1) throw t[1];
      return t[1];
    },
    trys: [],
    ops: []
  },
    f,
    y,
    t,
    g;
  return g = {
    next: verb(0),
    "throw": verb(1),
    "return": verb(2)
  },
    typeof Symbol === "function" && (g[Symbol.iterator] = function () {
      return this;
    }),
    g;
  function verb(n) {
    return function (v) {
      return step([n, v]);
    };
  }
  function step(op) {
    if (f) throw new TypeError("Generator is already executing.");
    while (_) try {
      if (f = 1, y && (t = y[op[0] & 2 ? "return" : op[0] ? "throw" : "next"]) && !(t = t.call(y, op[1])).done) return t;
      if (y = 0, t) op = [0, t.value];
      switch (op[0]) {
        case 0:
        case 1:
          t = op;
          break;
        case 4:
          _.label++;
          return {
            value: op[1],
            done: false
          };
        case 5:
          _.label++;
          y = op[1];
          op = [0];
          continue;
        case 7:
          op = _.ops.pop();
          _.trys.pop();
          continue;
        default:
          if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) {
            _ = 0;
            continue;
          }
          if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) {
            _.label = op[1];
            break;
          }
          if (op[0] === 6 && _.label < t[1]) {
            _.label = t[1];
            t = op;
            break;
          }
          if (t && _.label < t[2]) {
            _.label = t[2];
            _.ops.push(op);
            break;
          }
          if (t[2]) _.ops.pop();
          _.trys.pop();
          continue;
      }
      op = body.call(thisArg, _);
    } catch (e) {
      op = [6, e];
      y = 0;
    } finally {
        f = t = 0;
      }
    if (op[0] & 5) throw op[1];
    return {
      value: op[0] ? op[1] : void 0,
      done: true
    };
  }
};
var sleep = function (time) {
  return new Promise(function (resolve) {
    return setTimeout(function () {
      return resolve();
    },
      time);
  });
};


function aaa() {
  return __awaiter(this, void 0, void 0,
    function () {
      return __generator(this,
        function (_a) {
          switch (_a.label) {
            case 0:
              return [4
                /*yield*/
                , sleep(100)];
            case 1:
              _a.sent();
              return [2
                /*return*/
              ];
          }
        });
    });
}
aaa();