TypeCell, open source TypeScript notebooks live programming environment

  for (let i = 0; i < 10;|) {}
                         ^ cursor

  type Lazy<A> = () => A;
  const lazy = <A,>(f: Lazy<A>) => {
    let thunk: Lazy<A> = () => { throw null; }
    thunk = () => {
      const y = f();
      thunk = () => y
      return y;
    };
    return thunk;
  };
  const tap = <A,B>(f: Lazy<(a: Lazy<A>) => Lazy<B>>, a: Lazy<A>): Lazy<B> => 
    lazy(() => f()(a)());
  
  const ap = (f: any, a: any): any => tap<any,any>(f, a);
  
  const y = <A,>(f : (a: Lazy<A>) => Lazy<A>): Lazy<A> => ap(((x: any) => ap(ap(f, x), x)),((x: any) => ap(ap(f,x),x)));
  
  type Cat = {
    name: string,
    friend: Cat,
    prefersDryFood: boolean,
    foodPerWeek: number
  };
  export const cat = y<Cat>(self => lazy(() => ({
    name: "lol",
    friend: self(),
    prefersDryFood: false,
    foodPerWeek: 4,
  })))();

https://jasmcole.com/2021/05/19/matslab/

https://jasmcole.github.io/Pages/MaTSlab

> Something went wrong: TypeError: Cannot read properties of null (reading 'useRef')

Appears to be an issue with the charting library used here at a glance?

Well... presses Ctrl-Shift-i ...I found an easier way to run some code :)

[0]: https://vadosware.io/post/the-future-of-free-and-open-source...

I use Quokka.js but I hate that the free version is almost useless