import React from 'react';
import { useForm } from 'react-hook-form';
import { ioTsResolver } from '@hookform/resolvers/io-ts';
import t from 'io-ts';
// you don't have to use io-ts-types but it's very useful
import tt from 'io-ts-types';

const schema = t.type({
  username: t.string,
  age: tt.NumberFromString,
});

const App = () => {
  const { register, handleSubmit } = useForm({
    resolver: ioTsResolver(schema),
  });

  return (
    <form onSubmit={handleSubmit((d) => console.log(d))}>
      <input name="username" ref={register} />
      <input name="age" type="number" ref={register} />
      <input type="submit" />
    </form>
  );
};

export default App;