Function diff

src/ink/screen.ts:1459–1473

(
  prev: Screen,
  next: Screen,
)

 * Production code should use diffEach() to avoid allocations.
 */
export function diff(
  prev: Screen,
  next: Screen,
): [point: Point, removed: Cell | undefined, added: Cell | undefined][] {
  const output: [Point, Cell | undefined, Cell | undefined][] = []
  diffEach(prev, next, (x, y, removed, added) => {
    // Copy cells since diffEach reuses the objects
    output.push([
      { x, y },
      removed ? { ...removed } : undefined,
      added ? { ...added } : undefined,
    ])
  })
  return output
}

type DiffCallback = (
  x: number,