cocos-engine/docs/contribution/modules.md

Modules

Public modules

Modules under /exports are considered as public modules. Only public modules are visible to users. Other modules transitively imported from public modules are private.

The module 'cc' is a module which export all from specific public modules:

/* The source of module 'cc', for explanation purpose only */

for (const <module> in <selected-modules>) {
    export * from '<module>';
}

The <selected-modules> are public modules decided to be included in 'cc', by users.

Modules public only to Editor

Modules under /editor/exports are considered as modules public only to Cocos Creator Editor.

Add module export

If you want to expose a new API to users, either directly or transitively export it into one of the public modules.

For example, you want to expose a Mesh(declared in /cocos/core/assets/mesh.ts) to users. First, decide which public module you want it be in. Let's say /exports/base module.

You can directly export it at /exports/base module:

// At /exports/base.ts
export { Mesh } from '../cocos/core/assets/mesh';

Since /exports/base exports all from /cocos/core which exports all from /cocos/core/assets, you can also export it at /cocos/core/assets.

// At /cocos/core/assets/index.ts
export { Mesh } from './mesh';

If your API need to be in a brand new public module, you need to create the new public module.

Create public module

Creating a public module is simply add a module file under /exports.

Besides this, you need to config the category of the public module and whether the public module is defaulted, etc.

Take a look at the /cc.config.json. The features field is the name(s) of public modules.