Avoid the declaration of empty interfaces

Docs > Code Analysis > Static Analysis Rules > Avoid the declaration of empty interfaces

This page is not yet available in Spanish. We are working on its translation.
If you have any questions or feedback about our current translation project, feel free to reach out to us!

Metadata

ID: typescript-code-style/no-empty-interface

Language: TypeScript

Severity: Notice

Category: Best Practices

Description

Do not use empty interfaces.

Non-Compliant Code Examples

interface Foo {}
interface Foo extends {}
interface Bar extends Foo {}
interface Foo extends Array<number> {}
interface Foo extends Array<number | {}> {}
interface Foo extends Array<Bar> {}
interface Foo extends R {}
interface Foo<T> extends Bar<T> {}
declare module FooBar { type Baz = typeof baz; export interface Bar extends Baz {} }
interface Foo {

}

Compliant Code Examples

interface Foo { name: string; }
interface Foo { name: string; }
interface Bar { age: number; }

// valid because extending multiple interfaces can be used instead of a union type
interface Baz extends Foo, Bar {}
interface Foo { name: string; }
interface Foo { props: string; }
class Bar {}