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Package detail

reserved-identifiers

sindresorhus593.7kMIT1.0.0TypeScript support: included

Provides a list of reserved identifiers for JavaScript

reserved, identifiers, keywords, words, restricted, javascript, ecmascript, identifier, variable, function, property, set

readme

reserved-identifiers

Provides a list of reserved identifiers for JavaScript

It assumes the latest JavaScript version (ES2023) and module context. Supporting older JavaScript versions is a non-goal.

Install

npm install reserved-identifiers

Usage

import reservedIdentifiers from 'reserved-identifiers';

const identifiers = reservedIdentifiers();
const isReserved = identifier => identifiers.has(identifier);

console.log(isReserved('await'));
//=> true

API

reservedIdentifiers(options?)

Returns a Set with the identifiers.

options

Type: object

includeGlobalProperties

Type: boolean\ Default: false

Include the global properties globalThis, Infinity, NaN, and undefined. Although not officially reserved, they should typically not be used as identifiers.

  • is-identifier - Check if a string is a valid JavaScript identifier