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@slashlab/numerik-js

v1.0.0

Published

Validate and parse Polish identification numbers: PESEL, NIP, REGON, KRS, NRB, IBAN, VAT-EU, ID card, and passport

Readme

numerik-js

License Tests CodeRabbit Bundle size npm npm downloads

Validate and parse Polish identification numbers — PESEL, NIP, REGON, KRS, NRB, VAT-EU, IBAN, ID Card, and Passport. Rich value objects, detailed error reasons, zero production dependencies. TypeScript-first.

JavaScript/TypeScript port of slashlab/numerik (PHP).

Installation

npm install @slashlab/numerik-js
# or
pnpm add @slashlab/numerik-js

Quick Start

import { Numerik } from '@slashlab/numerik-js'

// Simple boolean check
Numerik.pesel().isValid('92060512186')  // true
Numerik.nip().isValid('5260250274')     // true

// Rich validation result with failure reasons
const result = Numerik.pesel().validate('92060512185')  // wrong checksum
result.isFailed()                         // true
result.getFirstFailure().reason           // ValidationFailureReason.InvalidChecksum

// Parse to value object
const pesel = Numerik.pesel().parse('92060512186')
pesel.getBirthDate()    // Date object: 1992-06-05
pesel.getGender()       // Gender.Female
pesel.isAdult()         // true

// Try-parse (returns null on failure instead of throwing)
const parsed = Numerik.nip().tryParse('5260250274')
parsed?.getFormatted()  // '526-025-02-74'

Strict mode

All identifiers accept an optional strict flag (default: true). In non-strict mode formatting variations (spaces, dashes) are accepted:

Numerik.nip(false).isValid('526 025 02 74')  // true
Numerik.nip(true).isValid('526 025 02 74')   // false

Zod integration

import { peselSchema, nipParseSchema } from '@slashlab/numerik-js/zod'
import { z } from 'zod'

const schema = z.object({
  pesel: peselSchema(),           // validates, keeps string
  nip: nipParseSchema(),          // validates and transforms to Nip value object
})

Supported identifiers

| Group | Identifier | Class | | -------- | ---------- | -------------------- | | Personal | PESEL | PeselIdentifier | | Personal | ID Card | IdCardIdentifier | | Personal | Passport | PassportIdentifier | | Tax | NIP | NipIdentifier | | Tax | VAT-EU | VatEuIdentifier | | Business | REGON | RegonIdentifier | | Business | KRS | KrsIdentifier | | Banking | NRB | NrbIdentifier | | Banking | IBAN | IbanIdentifier |

Changelog

See CHANGELOG.md.

Contributing

See CONTRIBUTING.md.

Security

See SECURITY.md.

License

MIT — see LICENSE.


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