Intersection

const · packages/primitives/src/observers/intersection.ts:17

const Intersection: Mount.MountDefinitionNoArgs<
  'Intersection',
  {
    readonly _tag: 'IntersectionChanged'
    readonly isIntersecting: boolean
    readonly ratio: number
  }
>

Element visibility as a Mount: IntersectionObserver reports viewport crossings as Messages for the element carrying this Mount. No observer (SSR, old browser) emits nothing instead of throwing.

In the guides

• Find one by the jobPrimitives / foldkit-primitives
• The mapPrimitives / foldkit-primitives
• foldkit-primitives/observersPrimitives / Observers
• Start with one: an element's sizePrimitives / Observers