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Type-safe carousel

@RiccardoOdone•Suggest a tip•

Instead of keeping the index and array separated, use a zip list.

type SlideDeck = {
  slides: Slide[],
  selected: number,
}

const carousel: SlideDeck = {
  slides: [], // ⛔️ There should be at least one
  selected: -10, // ⛔️ WTH?
}

type SlideDeck = {
  before: Slide[],
  current: Slide,
  after: Slide[],
} // ✅ Always one slide with 0 or more before and after
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