Function getMultiInternalSlots

packages/ecma402-abstract/utils.ts:44–64

(
  map: WeakMap<Instance, Internal>,
  pl: Instance,
  ...fields: Field[]
)

}

export function getMultiInternalSlots<
  Instance extends object,
  Internal extends object,
  Field extends keyof Internal,
>(
  map: WeakMap<Instance, Internal>,
  pl: Instance,
  ...fields: Field[]
): Pick<Internal, Field> {
  const slots = map.get(pl)
  if (!slots) {
    throw new TypeError(`${pl} InternalSlot has not been initialized`)
  }
  return fields.reduce(
    (all, f) => {
      all[f] = slots[f]
      return all
    },
    Object.create(null) as Pick<Internal, Field>
  )
}

export interface LiteralPart {
  type: 'literal'