BellaJS

A lightweight, functional utility library for Deno, Node.js, and Bun.

Features

• Type checking and validation
• String processing and similarity
• Array, object, and functional utilities
• Date, number, and secure random utilities
• TTL cache, helper utilities, and ranking algorithms

Installation

Deno

deno add jsr:@pwshub/bellajs

Node.js / Bun

pnpm i jsr:@pwshub/bellajs
# or
vlt install jsr:@pwshub/bellajs
# or
bunx jsr add @pwshub/bellajs
# or
npx jsr add @pwshub/bellajs

Alternatively, install from npm:

pnpm i @pwshub/bellajs
# or
bun add @pwshub/bellajs
# or
vlt add @pwshub/bellajs
# or
npm install @pwshub/bellajs

Browser

<script type="module">
import { genid } from "https://esm.sh/@pwshub/bellajs";
</script>

Quick Start

import {
  clone,
  formatDate,
  formatRelativeTime,
  genid,
  maybe,
  pipe,
} from "@pwshub/bellajs";

// Safe null handling with Maybe
const email = maybe(user)
  .map((u) => u.profile)
  .map((p) => p.email)
  .orElse(() => "default@example.com")
  .value();

// Function composition
const process = pipe(
  (data: string[]) => data.filter((x) => x.length > 3),
  (data) => data.map((x) => x.toUpperCase()),
  (names) => names.join(", "),
);

// Generate secure random IDs
const id = genid(16, "user_"); // 'user_aB3xY9kL2mN5pQ7r'

// Format dates with multi-language support
formatDate(new Date(), "vi"); // "20:34:28, 3 thg 1, 2026"
formatRelativeTime(Date.now() - 300000, "ja"); // "5 分前"

Documentation

Core Modules

Module	Functions	Description
Detection	15 functions	Type checking utilities
String	20 functions	Text manipulation and analysis
Random	2 functions	Cryptographically secure random generation
Date	7 functions	Date formatting and time calculations
Array	15 functions	Array utilities and transformations
Object	2 functions	Deep cloning and property copying
Functional	4 functions	compose, pipe, curry, maybe
Number	2 functions	Number formatting utilities
Similarity	5 functions	String comparison and similarity
Store	1 function	In-memory key-value store with TTL
Utility	1 function	Property definition helper
Rating	6 functions	Wilson Score, Bayesian Average, time-decay ratings

75 functions total.

Examples by Use Case

Safe Property Access

import { maybe } from "@pwshub/bellajs";

const email = maybe(user)
  .map((u) => u.profile)
  .map((p) => p.contact)
  .map((c) => c.email)
  .orElse(() => "default@example.com")
  .value();

Multi-language Text Processing

import {
  formatDate,
  formatRelativeTime,
  getWordCount,
  truncateByChar,
  truncateByWord,
} from "@pwshub/bellajs";

formatDate(new Date(), "en"); // "Jan 3, 2026, 8:34:28 PM"
formatDate(new Date(), "vi"); // "20:34:28, 3 thg 1, 2026"
formatDate(new Date(), "ja"); // "2026/1/3 20:34:28"

formatRelativeTime(Date.now() - 3600000, "en"); // "1 hour ago"
formatRelativeTime(Date.now() - 3600000, "vi"); // "1 giờ trước"

getWordCount("Hello world"); // 2
getWordCount("こんにちは世界"); // 2

truncateByWord("Hello world this is a test", 3); // "Hello world this..."
truncateByChar("👨‍👩‍👧‍👦abc", 3); // "👨‍👩‍👧‍👦ab..."

Secure Random Generation

import { genid, randomInt } from "@pwshub/bellajs";

genid(); // 'aB3xY9kL2mN5pQ7rS8tU0vW1xY2zA3bC' (32 chars)
genid(16); // 'kL2mN5pQ7rS8tU0v' (16 chars)
genid(16, "user_"); // 'user_aB3xY9kL2mN5p'

randomInt(100); // 0–100

Caching Without Redis

import { memstore } from "@pwshub/bellajs";

const cache = memstore(300); // 5-minute default TTL

cache.set("user:1", { name: "John", email: "john@example.com" });
const user = cache.get("user:1");

cache.set("session:abc", { userId: 1 }, 3600); // custom TTL: 1 hour

for (const [key, value] of cache.entries()) {
  console.log(key, value);
}

Function Pipelines

import { compose, curry, pipe } from "@pwshub/bellajs";

const processUser = pipe(
  (user: { profile: { settings: { theme: string } } }) => user.profile,
  (profile) => profile.settings,
  (settings) => settings.theme,
);

const analyze = compose(
  (result: string) => result.toUpperCase(),
  (data: string[]) => data.join("-"),
  (items: string[]) => items.filter((x) => x.length > 0),
);

const add = (a: number, b: number) => a + b;
const curriedAdd = curry(add);
curriedAdd(5)(3); // 8

Array Transformations

import {
  chunk,
  difference,
  flatten,
  groupBy,
  intersection,
  zip,
} from "@pwshub/bellajs";

chunk([1, 2, 3, 4, 5], 2); // [[1,2], [3,4], [5]]
flatten([1, [2, [3, [4]]]], 2); // [1, 2, 3, [4]]
difference([1, 2, 3, 4], [2, 3]); // [1, 4]
intersection([1, 2, 3], [2, 3, 4]); // [2, 3]
zip([1, 2], ["a", "b"]); // [[1,'a'], [2,'b']]

Number Formatting

import { formatBytes, formatNumber } from "@pwshub/bellajs";

formatBytes(1024); // '1 KiB'
formatBytes(1234567890); // '1.15 GiB'
formatNumber(123.456); // '123.46'
formatNumber(99.9, 0); // '100'

Platform Support

Platform	Version	Support
Deno	2.0+	✅ Primary
Node.js	22+	✅ Full
Bun	1.0+	✅ Full
Browsers	Modern (ESM)	✅ Full

Development

# Run tests
deno test

# Run linter
deno lint

# Build npm package (via DNT)
deno task build

# Publish to JSR
deno publish

# Publish to npm (after building)
cd npm && npm publish

License

MIT