Wrap promise for React Suspense

readable.ts

export function readable<R, E = unknown>(
  promise: Promise<R>,
  onSuccess?: (result: R) => void,
  onError?: (error: E) => void)
{
  let status = 'pending';
  let result: R;
  const suspender = promise.then(result => {
    status = 'fulfilled';
    onSuccess && onSuccess(result);
    result = result;
  }, error => {
    status = 'rejected';
    onError && onError(error);
    result = error;
  });
  return {
    read() {
      if (status === 'pending') {
        throw suspender;
      } else if (status === 'fulfilled') {
        return result;
      } else {
        throw result;
      }
    }
  }
}