no-new-symbol

Disallow new operators with the Symbol object

✅

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

Symbol is not intended to be used with the new operator, but to be called as a function.

var foo = new Symbol("foo");
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This throws a TypeError exception.

Rule Details

This rule is aimed at preventing the accidental calling of Symbol with the new operator.

Examples

Examples of incorrect code for this rule:

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/*eslint no-new-symbol: "error"*/
/*eslint-env es6*/

var foo = new Symbol('foo');
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Examples of correct code for this rule:

Open in Playground

/*eslint no-new-symbol: "error"*/
/*eslint-env es6*/

var foo = Symbol('foo');

// Ignores shadowed Symbol.
function bar(Symbol) {
    const baz = new Symbol("baz");
}

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When Not To Use It

This rule should not be used in ES3/5 environments.

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 v2.0.0-beta.1.

Resources

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