export

💼 This rule is enabled in the following configs: recommended, typescript.

Rule DetailsCopy Anchor Link

A module may export each name once per declaration space, and has one default export. The rule reports a second export of a name that TypeScript rejects as a duplicate, and a second default export. It decides by the kind of each export, the way TypeScript's declaration-merging table does:

• A value (const/let/var, a destructured binding, a function, export { v }, a re-export, export * as ns) and a pure type (interface, type) live in different spaces, so export type Twilio beside export const Twilio is legal.
• Declarations that merge are legal: interface + interface, class + interface, enum + enum (when at most one of them omits its first member's initializer), and a namespace beside a function, class, enum, interface, type alias or namespace.
• A namespace that holds only types (interfaces, type aliases, const enums, namespaces of the same kind) declares no value, so it merges with any export of the name except export * as N. export const Status = … beside export namespace Status { export type Code = … } is legal.
• Every other pair is a duplicate, including a class or enum beside a type alias of the same name (both occupy the type space too) and an export specifier beside any value: export type { T as N } is an alias, and TypeScript rejects it beside export const N.
• export default, export { v as default } and export { default } from './m' are each a default export. export * from never re-exports a default.

Names inside export namespace A {} are scoped to A. Not reported: a re-export beside a pure type of the same name (legal when the re-exported binding is a value, which this file cannot see), and collisions between export * from modules (they need the other modules).

❌ IncorrectCopy Anchor Link

export const N = 1;
export function N() {}

const o = { a: 1 };
export const { a } = o;
export const a = 2;

export class Shape {}
export type Shape = { kind: string };

export default 1;
export { value as default };

✅ CorrectCopy Anchor Link

export type Twilio = ITwilio;
export const Twilio = ITwilio;

export interface Options {
  a: string;
}
export interface Options {
  b: number;
}

export function build() {}
export namespace build {
  export const version = 1;
}

export enum Color {
  Red = 0,
}
export enum Color {
  Blue = 1,
}

OptionsCopy Anchor Link

[]

ImplementationCopy Anchor Link

• Source Code
• Test Cases

OWASP FoundationCopy Anchor Link

• Category: A00:2021 - General Security

Use this rule

npm install -D oxlint-plugin-import-next

{  "jsPlugins": ["oxlint-plugin-import-next"],  "rules": {    "import-next/export": "error"  }}

import { defineConfig } from 'vite-plus';export default defineConfig({  lint: {    jsPlugins: ['oxlint-plugin-import-next'],    rules: {      'import-next/export': 'error',    },  },});