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consistent-indexed-object-style

Require or disallow the Record type.

🔒

Extending "plugin:@typescript-eslint/strict" in an ESLint configuration enables this rule.

🛠

Some problems reported by this rule are automatically fixable by the --fix ESLint command line option.

TypeScript supports defining object show keys can be flexible using an index signature. TypeScript also has a builtin type named Record to create an empty object defining only an index signature. For example, the following types are equal:

interface Foo {
  [key: string]: unknown;
}

type Foo = {
  [key: string]: unknown;
};

type Foo = Record<string, unknown>;

Keeping to one declaration form consistently improve code readability.

.eslintrc.cjs
module.exports = {
  "rules": {
    "@typescript-eslint/consistent-indexed-object-style": "warn"
  }
};

Options​

This rule accepts an options string of the following possible values:

type Options = "record" | "index-signature";

const defaultOptions: Options = ["record"];
  • "record" (default): only allow the Record type.
  • "index-signature": only allow index signatures.

record​

/* eslint @typescript-eslint/consistent-indexed-object-style: ["error", "record"] */

interface Foo {
  [key: string]: unknown;
}

type Foo = {
  [key: string]: unknown;
};

index-signature​

/* eslint @typescript-eslint/consistent-indexed-object-style: ["error", "index-signature"] */

type Foo = Record<string, unknown>;

Resources​