React_dom_development 在 Deno React 项目中未定义

Question

I wanted to try out Deno, so I decided to make a simple single-page React app.我想尝试一下 Deno，所以我决定制作一个简单的单页 React 应用程序。 But, when I try to pull in ReactDOM from the CDN, I get a console error: react_dom_development_js_2 is undefined .但是，当我尝试从 CDN 中提取 ReactDOM 时，我得到一个控制台错误： react_dom_development_js_2 is undefined 。

I think what's going on is it can't resolve the ReactDOM CDN, but I can reach it from my browser?我认为发生了什么是它无法解析 ReactDOM CDN，但我可以从我的浏览器访问它？ I also tried replacing it with what the browser resolves it to ( https://unpkg.com/react-dom@16.13.1/umd/react-dom.development.js ), but I still end up with the same error.我还尝试用浏览器将其解析为（ https://unpkg.com/react-dom@16.13.1/umd/react-dom.development.js ）替换它，但我仍然遇到同样的错误。 Maybe I'm using the deno bundle wrong?也许我用错了deno bundle ？

index.jsx索引.jsx

import { React } from "https://unpkg.com/react@16/umd/react.development.js";
import { ReactDOM } from "https://unpkg.com/react-dom@16/umd/react-dom.development.js";

ReactDOM.render(<p>Hello</p>, document.findElementById("app"));

index.html索引.html

<html>
  <head>
    <title>Test with Deno</title>
  </head>
  <body>

    <div id="app"></div>
    <script src="index.bundle.js"></script>
  </body>
</html>

I run deno bundle index.jsx index.bundle.js to create my bundle,我运行deno bundle index.jsx index.bundle.js来创建我的包，

index.bundle.js index.bundle.js

// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.

// This is a specialised implementation of a System module loader.

// @ts-nocheck
/* eslint-disable */
let System, __instantiateAsync, __instantiate;

(() => {
  const r = new Map();

  System = {
    register(id, d, f) {
      r.set(id, { d, f, exp: {} });
    },
  };

  async function dI(mid, src) {
    let id = mid.replace(/\.\w+$/i, "");
    if (id.includes("./")) {
      const [o, ...ia] = id.split("/").reverse(),
        [, ...sa] = src.split("/").reverse(),
        oa = [o];
      let s = 0,
        i;
      while ((i = ia.shift())) {
        if (i === "..") s++;
        else if (i === ".") break;
        else oa.push(i);
      }
      if (s < sa.length) oa.push(...sa.slice(s));
      id = oa.reverse().join("/");
    }
    return r.has(id) ? gExpA(id) : import(mid);
  }

  function gC(id, main) {
    return {
      id,
      import: (m) => dI(m, id),
      meta: { url: id, main },
    };
  }

  function gE(exp) {
    return (id, v) => {
      v = typeof id === "string" ? { [id]: v } : id;
      for (const [id, value] of Object.entries(v)) {
        Object.defineProperty(exp, id, {
          value,
          writable: true,
          enumerable: true,
        });
      }
    };
  }

  function rF(main) {
    for (const [id, m] of r.entries()) {
      const { f, exp } = m;
      const { execute: e, setters: s } = f(gE(exp), gC(id, id === main));
      delete m.f;
      m.e = e;
      m.s = s;
    }
  }

  async function gExpA(id) {
    if (!r.has(id)) return;
    const m = r.get(id);
    if (m.s) {
      const { d, e, s } = m;
      delete m.s;
      delete m.e;
      for (let i = 0; i < s.length; i++) s[i](await gExpA(d[i]));
      const r = e();
      if (r) await r;
    }
    return m.exp;
  }

  function gExp(id) {
    if (!r.has(id)) return;
    const m = r.get(id);
    if (m.s) {
      const { d, e, s } = m;
      delete m.s;
      delete m.e;
      for (let i = 0; i < s.length; i++) s[i](gExp(d[i]));
      e();
    }
    return m.exp;
  }

  __instantiateAsync = async (m) => {
    System = __instantiateAsync = __instantiate = undefined;
    rF(m);
    return gExpA(m);
  };

  __instantiate = (m) => {
    System = __instantiateAsync = __instantiate = undefined;
    rF(m);
    return gExp(m);
  };
})();

System.register(
  "index",
  [
    "https://unpkg.com/react@16/umd/react.development.js",
    "https://unpkg.com/react-dom@16/umd/react-dom.development.js",
  ],
  function (exports_1, context_1) {
    "use strict";
    var react_development_js_1, react_dom_development_js_1;
    var __moduleName = context_1 && context_1.id;
    return {
      setters: [
        function (react_development_js_1_1) {
          react_development_js_1 = react_development_js_1_1;
        },
        function (react_dom_development_js_1_1) {
          react_dom_development_js_1 = react_dom_development_js_1_1;
        },
      ],
      execute: function () {
        react_dom_development_js_1.ReactDOM.render(
          react_development_js_1.React.createElement("p", null, "Hello"),
          document.findElementById("app"),
        );
      },
    };
  },
);

__instantiate("index");

Answer 1

The issue here is due to the typical React and ReactDOM packages being written as commonJS packages.这里的问题是由于典型的 React 和 ReactDOM 包被编写为 commonJS 包。

Deno by default requires all modules to be written using ES Modules (ESM). Deno 默认要求所有模块都使用 ES Modules (ESM) 编写。 https://github.com/pikapkg/react is a build of React and ReactDOM that use ESM, so they should be importable in Deno. https://github.com/pikapkg/react是使用 ESM 的 React 和 ReactDOM 的构建，因此它们应该可以在 Deno 中导入。 link with CDN与 CDN 链接

There is a standard library module in deno that lets you use commonJS modules, though you'll need to be careful with them especially if they require node specific functionality: https://deno.land/std/node#commonjs-module-loading deno 中有一个标准库模块可让您使用 commonJS 模块，但您需要小心使用它们，特别是如果它们需要特定于节点的功能： https://deno.land/std/node#commonjs-module-loading

Answer 2

TypeScript does not allow imports from html or that end in a file extension. TypeScript 不允许从 html 或以文件扩展名结尾的导入。 So for now you can ignore them using // @ts-ignore which will allow deno to work.所以现在你可以使用// @ts-ignore它们，这将允许 deno 工作。

There is a visual studio code extension for deno but at the time of writing it seems to be a bit unstable. deno 有一个 Visual Studio 代码扩展，但在撰写本文时它似乎有点不稳定。 If and when its working correctly you would be able to config deno to work on a per project basis by defining a settings folder in the root of your project eg .vscode/settings.json .如果并且当它正常工作时，您可以通过在项目的根目录中定义一个设置文件夹来配置 deno 以在每个项目的基础上工作，例如.vscode/settings.json 。

{
  "deno.enable": true
}

React_dom_development 在 Deno React 项目中未定义

问题描述

2 个解决方案

解决方案1
2 已采纳 2020-05-30 20:03:25

解决方案2
0 2020-05-30 19:43:53

React_dom_development 在 Deno React 项目中未定义

问题描述

2 个解决方案

解决方案1 2 已采纳 2020-05-30 20:03:25

解决方案2 0 2020-05-30 19:43:53

解决方案1
2 已采纳 2020-05-30 20:03:25

解决方案2
0 2020-05-30 19:43:53