Yup

Overview

Yup is a schema validation library for JavaScript. Define schemas declaratively, validate data, and get detailed error messages. Works with Formik, react-hook-form, and standalone. TypeScript-first with type inference.

Instructions

Step 1: Schemas

import * as yup from 'yup'

const userSchema = yup.object({
  name: yup.string().min(2).max(100).required(),
  email: yup.string().email().required(),
  age: yup.number().positive().integer().min(13).max(120),
  role: yup.string().oneOf(['admin', 'member', 'viewer']).default('member'),
  tags: yup.array().of(yup.string()).min(1).max(10),