Function getCreateFunction

src/common/definable.ts:230–246

(
  getFunction: (store: Store) => Thing,
  initFunction?: (thing: Thing) => void,
)

      ((): RowValue => defaultCellValue ?? (EMPTY_STRING as any as RowValue)));

export const getCreateFunction = <
  Thing extends
    Metrics | Middleware | Indexes | Relationships | Checkpoints | Queries,
>(
  getFunction: (store: Store) => Thing,
  initFunction?: (thing: Thing) => void,
): ((store: Store) => Thing) => {
  const thingsByStore: WeakMap<Store, Thing> = new WeakMap();
  return (store: Store): Thing => {
    if (!thingsByStore.has(store)) {
      thingsByStore.set(store, getFunction(store));
    }
    const thing = thingsByStore.get(store) as Thing;
    initFunction?.(thing);
    return thing;
  };
};