class Comp<T extends Record<string, any>> extends VueComponent<
  { items: T; keyPath: keyof T; cols: Array<keyof T> },

  // emits
  {
    select(item: T): void;
    "update:modelValue"(item: T): void;
    cellClicked(col: keyof T, item: T);
  },

  // slots https://github.com/vuejs/rfcs/pull/192
  {
    [K: `head:${keyof T & string}`]: { a: number };
    [Y: `item:${keyof T & string}`]: { b: string };
  }
>