Basic - Zod

yarn add zod

import { z } from "zod";
 
const User = z.object({
    id: z.number(),
    username: z.string().min(1),
    desc: z.string().max(255),
    email: z.string().email(),
    banned: z.boolean(),
    birthday: z.date(),
 
    // remarks: string | null
    remarks: z.string().nullable(), 
 
    // username?: string | undefined
    otherRemarks: z.string().optional()
});
 
User.parse({ 
    id: 1,
    username: "tom",
    desc: "Hi, I am Tom.",
    email: "tom@gmail.com",
    banned: false,
    birthday: new Date(),
    remarks: null
});
 
type UserScheme = z.infer<typeof User>;

import { z } from "zod";
 
const StudentUser = User.extend({
    class: z.string(),
});

import { z } from "zod";
 
// Keep this type only
const JustTheEmail = User.pick({ 
    email: true
});
 
// { email: string }
 
// Remove these types
const Readableuser = User.omit({ 
    id: true,
    banned: true,
    remarks: true,
    otherRemarks: true
});
 
// {
//   username: string
//   desc: string
//   email: string
// }