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我发现它不可能做的所有未来4件事情togother：使用打字稿异步等待中的Node.js
- 写作的Node.js
- 写作打字稿
- 使用
async await - 调试容易
说明：
我有一个用TypeScript编写的Node.js项目，我打算使用async await。
现在的问题是，如果我transpile到ES6，作为disscused这里的进口关键词产生“意外的标记导入”错误：ES6 import and export are not supported in Node.js，而如果我transpile到ES5的async await转成不可读代码：
这：
///<reference path="../typings/modules/bluebird/index.d.ts" />
///<reference path="../typings/modules/mongodb/index.d.ts" />
import * as Promise from 'bluebird';
import { MongoClient, Db } from 'mongodb';
import {Campaign} from "../classes/Campaign";
export async function getCampaigns(): Campaign[] {
try{
var db = await connect();
var campaigns: Campaign[] = await db.collection("campaigns").find().toArray();
return campaigns;
}
catch (err){
console.log(err);
}
}
async function connect(): Promise<Db> {
return await MongoClient.connect("mongodb://localhost:27017/db");
}
变成这样：
"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
return new (P || (P = 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 P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments)).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t;
return { next: verb(0), "throw": verb(1), "return": verb(2) };
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 };
}
};
///<reference path="../typings/modules/bluebird/index.d.ts" />
///<reference path="../typings/modules/mongodb/index.d.ts" />
var Promise = require("bluebird");
var mongodb_1 = require("mongodb");
function getCampaigns() {
return __awaiter(this, void 0, void 0, function() {
var db, campaigns, err_1;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
_a.trys.push([0, 3, , 4]);
return [4 /*yield*/, connect()];
case 1:
db = _a.sent();
return [4 /*yield*/, db.collection("campaigns").find().toArray()];
case 2:
campaigns = _a.sent();
return [2 /*return*/, campaigns];
case 3:
err_1 = _a.sent();
console.log(err_1);
return [3 /*break*/, 4];
case 4: return [2 /*return*/];
}
});
});
}
exports.getCampaigns = getCampaigns;
function connect() {
return __awaiter(this, void 0, Promise, function() {
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, mongodb_1.MongoClient.connect("mongodb://localhost:27017/db")];
case 1: return [2 /*return*/, _a.sent()];
}
});
});
}
我该如何解决这个矛盾？