ECMAScript modulesとCommonJS modulesの使い分け

個人の感想です。

規約

• 相対パスは ECMAScript modules で import/export
• それ以外は Common JS で require/module.exports

意味

• 内界 - プロジェクト内のコードはECMAScript modulesでやり取り
• 外界 - npmパッケージを require や、package.jsonの "main" へのexportはCommonJSでやり取り

例

const fs = require("fs");
const path = require("path");
const mkdirp = require("mkdirp");
const Promise = require("bluebird");
const debug = require("debug")("textlint:cli");
import options from "./options";
import TextLintEngine from "./textlint-engine";
import TextFixEngine from "./textfix-engine";
import Config from "./config/config";
import configInit from "./config/config-initializer";
import TextLintFixer from "./fixer/textlint-fixer";
import Logger from "./util/logger";

• https://github.com/textlint/textlint/blob/6fd9273cf0bae467b8739343f3492a6e029a8410/src/cli.js

その他

• 8.1.1.5 Module Environment Records
• whatwg/loader: Loader Standard
• 16. Modules
• ES6 module loading: More complicated than you think - NCZOnline
• ES6 Module Detection in Node · nodejs/node Wiki
• TypeScript-Handbook/Namespaces and Modules.md at master · Microsoft/TypeScript-Handbook
• Typings for NPM Packages · TypeScript
• ES6 in Practice
• Webpack 2 Tree Shaking Configuration — Modus Create: Front End Development — Medium