主入口点导出

¥Main entry point export

当编写新包时，建议使用 "exports" 字段：

¥When writing a new package, it is recommended to use the "exports" field:

{
  "exports": "./index.js"
} 拷贝

定义 "exports" 字段后，包的所有子路径都将被封装，并且不再可供导入者使用。例如，require('pkg/subpath.js') 抛出 ERR_PACKAGE_PATH_NOT_EXPORTED 错误。

¥When the "exports" field is defined, all subpaths of the package are encapsulated and no longer available to importers. For example, require('pkg/subpath.js') throws an ERR_PACKAGE_PATH_NOT_EXPORTED error.

这种导出封装为工具的包接口以及处理包的 semver 升级提供了更可靠的保证。它不是一个强封装，因为直接要求包的任何绝对子路径（例如 require('/path/to/node_modules/pkg/subpath.js')）仍然会加载 subpath.js。

¥This encapsulation of exports provides more reliable guarantees about package interfaces for tools and when handling semver upgrades for a package. It is not a strong encapsulation since a direct require of any absolute subpath of the package such as require('/path/to/node_modules/pkg/subpath.js') will still load subpath.js.

当前所有受支持的 Node.js 版本和现代构建工具都支持 "exports" 字段。对于使用旧版本 Node.js 或相关构建工具的项目，可以通过在指向同一模块的 "exports" 旁边包含 "main" 字段来实现兼容性：

¥All currently supported versions of Node.js and modern build tools support the "exports" field. For projects using an older version of Node.js or a related build tool, compatibility can be achieved by including the "main" field alongside "exports" pointing to the same module:

{
  "main": "./index.js",
  "exports": "./index.js"
} 拷贝