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@zerodep/is-error

v2.1.8

Published

A utility to determine if a value is an Error or specific instance/subclass of an Error type.

Downloads

8

Readme

@zerodep/is-Error

version language types license

CodeFactor Known Vulnerabilities

OpenSSF Best Practices

A utility to determine if a value is an Error or specific instance/subclass of an Error type.

Full documentation is available at the zerodep.app page.

Signature

declare const isError: (value: unknown) => boolean;

Examples

All @zerodep packages support both ESM and CJS formats, each complete with Typescript typings.

// ESM
import { isError } from '@zerodep/is-error';

// CJS
const { isError } = require('@zerodep/is-error');
// Arrays
isError([]); // false
isError([1, 2, 3]); // false
isError(['a', 'b', 'c']); // false

// BigInts
isError(42n); // false
isError(0n); // false
isError(-0n); // false
isError(-42n); // false

// Booleans
isError(true); // false
isError(false); // false

// Class
isError(
  class SomeClass {
    constructor() {}
  }
); // false

// Dates
isError(new Date()); // false
isError(new Date('1970-01-01T12:00:00.000Z')); // false
isError(new Date('2099-12-31')); // false

// Empty
isError(null); // false
isError(undefined); // false

// Errors
isError(new Error('message')); // true
isError(new AggregateError([new Error('err1'), new Error('err2')], 'message')); // true

// Floats
isError(3.14); // false
isError(0.0); // false
isError(-0.0); // false
isError(-3.14); // false
isError(Math.E); // false
isError(Math.PI); // false
isError(Number.MIN_VALUE); // false

// Functions
isError(() => 'function'); // false
isError(async () => 'function'); // false

// Generators
isError(function* () {
  yield 'a';
}); // false
isError(async function* () {
  yield 'a';
}); // false

// Maps
isError(new Map()); // false
isError(new Map([['key1', 123]])); // false
isError(new Map([['key1', 'value1']])); // false

// Numbers
isError(Number.POSITIVE_INFINITY); // false
isError(Number.MAX_SAFE_INTEGER); // false
isError(Number.MAX_VALUE); // false
isError(3e8); // false
isError(42); // false
isError(1); // false
isError(0); // false
isError(-0); // false
isError(-1); // false
isError(-42); // false
isError(-3e8); // false
isError(Number.MIN_SAFE_INTEGER); // false
isError(Number.NEGATIVE_INFINITY); // false
isError(Number.NaN); // false

// POJOs
isError({}); // false
isError({ key: 'string' }); // false
isError({ key: 123 }); // false

// Promise
isError(new Promise(() => {})); // false
isError(new Promise.all([])); // false
isError(new Promise.allSettled([])); // false
isError(new Promise.race([])); // false
isError(Promise.resolve()); // false

// Regular Expression
isError(/[regex]+/gi); // false
isError(new RegExp('d', 'gi')); // false

// Sets
isError(new Set()); // false
isError(new Set([1, 2, 3])); // false
isError(new Set(['a', 'b', 'c'])); // false

// Strings
isError(''); // false
isError('a longer string'); // false
isError('1000n'); // false
isError('3e8'); // false
isError('42'); // false
isError('3.14'); // false
isError('0'); // false
isError('-0'); // false
isError('-3.14'); // false
isError('-42'); // false
isError('-3e8'); // false
isError('-1000n'); // false

// Symbols
isError(Symbol()); // false
isError(Symbol('name')); // false

// This
isError(this); // false
isError(globalThis); // false

// TypedArrays
isError(new Int8Array(2)); // false
isError(new Int16Array(2)); // false
isError(new Int32Array(2)); // false
isError(new Uint8Array(2)); // false
isError(new Uint16Array(2)); // false
isError(new Uint32Array(2)); // false
isError(new Uint8ClampedArray(2)); // false

isError(new BigInt64Array(2)); // false
isError(new BigUint64Array(2)); // false

isError(new Float32Array(2)); // false
isError(new Float64Array(2)); // false

isError(new SharedArrayBuffer(512)); // false

// WeakMap and WeakSet
isError(new WeakMap()); // false
isError(new WeakSet()); // false

ZeroDep Advantages

  • Zero npm dependencies - completely eliminates all risk of supply-chain attacks, decreases node_modules folder size
  • ESM & CJS - has both ecmascript modules and common javascript exports
  • Tree Shakable - built to be fully tree shakable ensuring your packages are the smallest possible size
  • Fully typed - typescript definitions are provided for every package for a better developer experience
  • Semantically named - package and method names are easy to grok, remember, use, and read
  • Documented - actually useful documentation with examples at zerodep.app
  • Intelligently Packaged - multiple npm packages of different sizes available allowing a menu or a-la-carte composition of capabilities
  • 100% Tested - all methods and packages are fully unit tested
  • Predictably Versioned - semantically versioned for peace-of-mind upgrading, this includes changelogs
  • MIT Licensed - permissively licensed for maximum usability