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no-dupe-keys

Disallow duplicate keys in object literals

✅ Recommended

The "extends": "eslint:recommended" property in a configuration file enables this rule

Multiple properties with the same key in object literals can cause unexpected behavior in your application.

var foo = {
    bar: "baz",
    bar: "qux"
};

Rule Details

This rule disallows duplicate keys in object literals.

Examples of incorrect code for this rule:

Open in Playground
/*eslint no-dupe-keys: "error"*/

var foo = {
    bar: "baz",
    bar: "qux"
};

var foo = {
    "bar": "baz",
    bar: "qux"
};

var foo = {
    0x1: "baz",
    1: "qux"
};

Examples of correct code for this rule:

Open in Playground
/*eslint no-dupe-keys: "error"*/

var foo = {
    bar: "baz",
    quxx: "qux"
};

Handled by TypeScript

It is safe to disable this rule when using TypeScript because TypeScript's compiler enforces this check.

Version

This rule was introduced in ESLint v0.0.9.

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