使用esScript-promise与TypeScript 2.1 ES5 Webpack(async/await)

Question

我尝试使用es6-promiseTypeScript 2.1.1定位ES5和webpack.

app.ts

import "es6-promise/auto";

export class Foo {
    bar() : Promise<string>{
        return Promise.resolve("baz");
    }
}

webpack.common.js

const path = require('path');
var webpack = require('webpack');

module.exports = {
    entry: {
        'app': './app.ts',
    },

    output: {
        path: 'dist/ie',
        filename: '[name].js'
    },

    resolve: {
        extensions: ['', '.ts', '.js']
    },

    devtool: 'source-map',

    module: {
        loaders: [
            {
                test: /\.ts$/,
                loaders: ['awesome-typescript-loader']
            },
        ]
    },
    plugins: [  
        new webpack.ProvidePlugin({
            Promise: 'imports?this=>global!exports?global.Promise!es6-promises'
        }),

    ]
};

的package.json

{
  "name": "foo",
  "ieArtifactName": "foo",
  "version": "3.0.0-1",
  "description": "...",
  "main": "src/app.ts",
  "author": {
    "name": "...",
    "email": "...",
    "url": "..."
  },
  "dependencies": {
    "@types/es6-promise": "0.0.32",
    "@types/jquery": "^2.0.34",
    "@types/underscore": "^1.7.34",
    "es6-promise": "^4.0.5",
    "es6-promise-promise": "^1.0.0",
    "es6-promises": "^1.0.10",
    "rxjs": "5.0.0-beta.12",
    "zone.js": "^0.6.23"
  },
  "devDependencies": {
    "awesome-typescript-loader": "=2.2.4",
    "clean-webpack-plugin": "^0.1.14",
    "css-loader": "^0.26.0",
    "exports-loader": "^0.6.3",
    "http": "0.0.0",
    "https": "^1.0.0",
    "imports-loader": "^0.6.5",
    "load-grunt-tasks": "^3.5.2",
    "node-static": "^0.7.9",
    "pug": "^2.0.0-beta6",
    "pug-html-loader": "^1.0.9",
    "raw-loader": "^0.5.1",
    "sass-loader": "^4.0.2",
    "style-loader": "^0.13.1",
    "typescript": "^2.1.1",
    "webpack": "^1.13.3",
    "webpack-dev-server": "^1.14.1",
    "webpack-merge": "^0.14.0"
  }
}

我使用命令行启动webpack

webpack --config config/webpack.common.js

行为如下:

• Webstorm 2016.3.1突出了一切.
• 编译运行
• 编译器显示2个错误

  ERROR in [default] D:...\app.ts:4:16找不到名字'Promise'.

我试过es6-promise,es6-promises,es6-promise-promise和一堆进口表情.

当我添加import {Promise} from "es6-promise"webstorm 时将其突出显示为未使用的导入,但错误消失了.是否可以使用针对ES5的Promise而无需导入？因为在将目标更改为ES6后,我必须触摸每个文件并删除导入.

异步问题

我的目标是能够使用async/await,因为我已经习惯了它来自C#并且我讨厌回调地狱.如果我将代码更改为

export class Foo {
    async bar() : Promise<string>{
        return "baz";
    }
}

编译器再次抱怨

找不到名字'承诺'.

添加导入import {Promise} from "es6-promise";会使情况变得更糟.

重复标识符'Promise'.编译器在包含异步函数的模块的顶级范围内保留名称"Promise".

Answer 1

您可以通过添加"es2015.promise"要包含在tsconfig.json中的库文件列表,使TypeScript编译器了解ES2015承诺:

{
    "compilerOptions": {
        "lib": [
            "dom",
            "es5",
            "scripthost",
            "es2015.promise"
        ]
    }
}

原生承诺仅在ES2015中引入,并且不在ES5中提供,而您目标是.这就是TypeScript编译器说它无法找到名称的原因Promise.由于您提供的是polyfill,因此将Promise在运行时提供.上述解决方案使TypeScript意识到了这一点.

编辑Sven-Michael

你甚至不需要Promise通过提供插件提供.你只需要import "es6-promise/auto";