isx

Tiny, intent-based string validation for JavaScript and TypeScript. Zero dependencies, extremely lightweight, and tree-shakeable.

🚀 Overview

isx is designed for developers who want clear, readable, and type-safe string validation. Instead of writing complex regex for every project, use isx to express your intent.

• Tiny: No dependencies, minimal footprint.
• Type-Safe: Written in TypeScript with full support for Type Guards and Assertion Functions.
• Modular: Only bundle what you use.

📦 Installation

npm install isx-intent
# or
yarn add isx-intent
# or
pnpm add isx-intent

🛠️ Usage

Boolean Validation (isx)

Returns true if valid, false otherwise. Acts as a Type Guard.

```typescript
import { isx } from 'isx-intent';

if (isx.email('[email protected]')) {
  // TypeScript knows value is a valid email string here
}

isx.url('https://google.com'); // true
isx.port(8080);               // true
isx.uuid('f47ac10b...');     // true

Assertion Validation (assert)

Throws a ValidationError if the check fails. Useful for flow control and early returns.

```typescript
import { assert } from 'isx-intent';

try {
  assert.email(userInput);
  // Proceed with confidence
} catch (error) {
  console.log(error.message); // "Invalid email address"
  console.log(error.code);    // "INVALID_EMAIL"
}

📚 API Reference

Identity & Web

• email(value): Validates email format.
• url(value): Validates URL format (supports localhost and ports).
• ip(value, version?): Validates IPv4 or IPv6.
• fqdn(value): Fully Qualified Domain Name.

Security & ID

• password(value, options?): Defaults to min length 8. Can require special chars.
• uuid(value): RFC4122 v4 UUID.
• ulid(value): Universal Unique Lexicographically Sortable Identifier.
• cuid(value): Collision-resistant IDs.
• mongodbId(value): MongoDB ObjectId format.

Commerce & Finance

• creditCard(value): Validates using Luhn algorithm.
• currency(value, codes?): ISO currency codes (USD, EUR, etc.).
• iban(value): International Bank Account Number format.

Utilities

• json(value): Checks if string is valid parsable JSON.
• semver(value): Semantic Versioning (e.g., 1.2.3-beta.1).
• port(value): Number between 0 and 65535.
• handle(value): Social handles (e.g., @username).
• macAddress(value): Standard MAC address format.
• hexColor(value), rgbColor(value), hslColor(value): CSS color formats.

🛡️ Error Handling

The assert API throws a ValidationError which extends the native Error class and includes a code property for programmatic handling.

```typescript
import { ValidationError } from 'isx-intent';

// ... inside a catch block
if (error instanceof ValidationError) {
  switch (error.code) {
    case 'INVALID_EMAIL': 
      // handle specific error
  }
}

📄 License

MIT © Hiren Tumbadiya