Hello, i haven't tried it but you should try import Rule from '@cesium133/forgjs'; tell me if this solves your problem

No it doesn’t

this worked for me can you give me more information i dont get the problem that you got

Are you sure you tried on ‘npx create-react-library’ I realised on the title I put the CRA that is the wrong one

can you tell me the steps you went thought i did:
1- npx create-react-library
2- named it pr
3- went to the pr folder
4- did npm i @cesium133/forgjs
5- changed the exemple component to use forgjs
6- did npm start

i didn't get any problem

1-npx create-react-library
2- pr
3- npm
4- typescript
5- cd pr
6- cd src
7- replace the content of index.tsx

import * as React from 'react';
import {Rule} from '@cesium133/forgjs';
import styles from './styles.css';

const ExampleComponent = ({ text }: any) => {
  const floatRule = new Rule(
    {
      type: 'float',
      min: 100,
    },
    null
  );
  const result = floatRule.test(200.3);
  console.log(result);

  return <div className={styles.test}>Example Component: {text}</div>;
};

export default ExampleComponent;

8- npm start

Error:

[!] Error: 'Rule' is not exported by node_modules/@cesium133/forgjs/index.js
https://github.com/rollup/rollup/wiki/Troubleshooting#name-is-not-exported-by-module
src/index.tsx (2:9)
1: import * as React from 'react';
2: import { Rule } from '@cesium133/forgjs';
            ^
3: import styles from './styles.css';

The folder you edit is the demo folder that is the project that run your library

Apparently imports dont work with type script you can use require it worked for me try this and tell me if you get errors: const { Rule } = require('@cesium133/forgjs');

Unfortunately is not correct! Import works really well with typescript. I tried to use it in a CRA create-react-app newtest —typescript.
Not sure what stop it to work over here instead

Did the require work for you ?

It create a circular recoursion on the demo. However I don’t think require is the best solution

Id keep looking. Please tell me if you find a fix for this