```ts
/** The text, cut to limit characters with an ellipsis when it is longer. */
export function truncate(text: string, limit: number): string {
  if (typeof limit !== 'number' || limit < 3) {
    throw new Error('limit must be a number greater than or equal to 3');
  }
  const sliced = text.slice(0, limit);
  return sliced.length === limit ? sliced : `${sliced.slice(0, -1)}...`;
}
```