Vanilla Quick Start

Install Core and validate a plain TypeScript model. The Vanilla JS Showcase follows the same pattern and then binds results to the DOM.

Install

npm install @validation-rules-engine/core

Define a policy

import type { ValidationPolicy, Validator, ValidatorHelper } from '@validation-rules-engine/core';

export class AccountPolicy implements ValidationPolicy {
  addValidations(helper: ValidatorHelper): Validator[] {
    return [
      helper.validateFor('name').isRequired('Name is required'),
      helper.validateFor('email')
        .isRequired('Email is required')
        .isEmail('Enter a valid email address')
    ];
  }
}

Execute with Core helpers

Adapters call Core for you. In a Vanilla JS (or other Core-only) app you register the policy, run validators, and read model.validationResults:

import { ValidatorHelper } from '@validation-rules-engine/core';
import { AccountPolicy } from './account-policy';

const policy = new AccountPolicy();
const helper = new ValidatorHelper();
const validators = policy.addValidations(helper);

const model = {
  name: '',
  email: 'not-an-email',
  validationResults: [] as unknown[]
};

// Showcase code evaluates validators and writes ValidationResult metadata onto the model.
// Open the live Vanilla JS Showcase to see field touch, blur, submit, and summary wiring.

Try it live

• Simple form
• Complex form
• Performance form

When to use an adapter instead

Choose @validation-rules-engine/angular or @validation-rules-engine/react when you need framework lifecycle integration, controlled-field helpers, or framework-native display strategies. Keep using Core-only policies either way.