Basepura

Introduction

Basepura is an encoding scheme that converts integers into human-readable strings while preventing accidental offensive words in Latin alphabet languages. This npm package provides a dependency-free TypeScript implementation.

Problem

Standard base-N encoding schemes (Base32, Base36, Base64 etc.) can inadvertently generate offensive substrings when creating public-facing identifiers. Crockford's Base32 partially addresses this but still permits problematic words like twat and merde. Removing vowels is insufficient as obscenities like zmrd (fucker in Czech/Slovak) and acronyms like BDSM remain possible. Digits also enable leetspeak variants (sh1t, 0rg4sm).

Solution

Basepura uses a carefully selected character set to minimize offensive word generation. The encoding has been verified against offensive terms in over 20 languages.

Basepura character set

BCDGHJKLNPQRSTWZbcdghjklnpqrstwz (32 characters)

Excluded characters

| Characters | Reason for exclusion | |------------|----------------------| | A, a | fag, twat... | | E, e | sex, merde... | | F, f | WTF, af... | | I, i | clit, dick... | | M, m | BDSM, zmrd... | | O, o | homo, sodomy... | | U, u | fuck, cunt... | | V, v | Resemble U, u | | X, x | xxx, shxt... | | Y, y | dirty, doggy... |

Installation

npm i basepura

Usage

import { encode, decode, isBasepura } from 'basepura';

// Encoding a bigint
const numberToEncode = 12345678901234567890n;
const encodedString = encode(numberToEncode);
console.log(`Encoded ${numberToEncode} to: ${encodedString}`);
// Encoded 12345678901234567890n to: QkjJPcgjcwDkd

// Validating a string
const validString = 'QkjJPcgjcwDkd';
const invalidString = 'Hello123';
console.log(`Is ${validString} valid Basepura? ${isBasepura(validString)}`);
// Is QkjJPcgjcwDkd valid Basepura? true
console.log(`Is ${invalidString} valid Basepura? ${isBasepura(invalidString)}`);
// Is Hello123 valid Basepura? false

// Decoding a string
const stringToDecode = 'QkjJPcgjcwDkd';
const decodedNumber = decode(stringToDecode);
console.log(`Decoded ${stringToDecode} to: ${decodedNumber}`); 
// Decoded QkjJPcgjcwDkd to: 12345678901234567890n

// Handling errors
try {
  decode('Invalid');
} catch (e) {
  console.error(e);
  // RangeError: Invalid character in input.
}

try {
  encode(-1n);
} catch (e) {
  console.error(e);
  // RangeError: Input must be a non-negative integer.
}

License

MIT