Menene bambanci tsakanin CommonJS da ES Modules a Node?

Question

Accepted Answer

Node yana goyan bayan **tsarin modules biyu**: **CommonJS (CJS)** — na asali, yana amfani da `require`/`module.exports` — da **ES Modules (ESM)** — na daidai, yana amfani da `import`/`export`. Suna bambanta a siyayya, halayin lodin, da haɗin gwiwa.

## CommonJS — na asali na Node

```js
// math.js
function add(a, b) { return a + b; }
module.exports = { add };

// app.js
const { add } = require("./math"); // synchronous, runtime
```

## ES Modules — na daidai

```js
// math.mjs (or .js with "type": "module")
export function add(a, b) { return a + b; }
export default something;

// app.mjs
import { add } from "./math.mjs"; // static, hoisted
```

## Bambance-bambancen mahimmanci

```text
                 CommonJS              ES Modules
Syntax           require/module.exports import/export
Loading          synchronous, runtime  static, hoisted
Top-level await  no                    yes
Tree-shaking     hard                  yes (statically analyzable)
File extension   .cjs / .js (default)  .mjs / .js with "type":"module"
__dirname/__filename available         not available (use import.meta.url)
```

## Ƙaƙƙarfan ESM

```json
// package.json
{ "type": "module" }  // now .js files are treated as ESM
```

Ko yi amfani da `.mjs` ɛstenshan a bayyani. Ba tare da wannan ba, Node yana bugi `.js` zuwa CommonJS.

## Haɗin gwiwan damuwa

```js
// ESM can import CommonJS:
import pkg from "some-cjs-lib"; // works (default import)

// CommonJS CANNOT require() a pure-ESM package (it's async):
const esm = require("esm-only-pkg"); // ❌ ERR_REQUIRE_ESM
// must use dynamic import: const esm = await import("esm-only-pkg");
```

Rugujewar: CJS ba zai iya `require()` paket ESM-only ba — abin damuwawa a juyawa. Kuma lura ESM ba ta da `__dirname` (yi amfani da `import.meta.url`).

## Menene mahalaccinsa

Sanin tsarin duka biyu shine abubuwa makawa don ainihin aikin Node: ESM shine gida (na daidai, tree-shakeable, top-level await, ɗin tunaninsa) da zaɓin daidai don sabuwar ayyuka, amma wataƙila babbar bangaren jiya-tasha npm da kodal da aka samu shine CommonJS.

Sanin bambance-bambancen siyayya, yadda ake ƙaƙƙarfan ESM (`"type": "module"`), da damuwar haɗin gwiwa (musamman CJS-can't-require-ESM) yana hana tsinkayen ruɗani da kuskure waɗa ke faruwa yayin haɗa su.