Function makeLazyPromise

packages/@stdlib/misc/src/promises.ts:85–99

(
  asyncFunc: () => PromiseLike<any>,
)

}

export function makeLazyPromise(
  asyncFunc: () => PromiseLike<any>,
): PromiseLike<any> {
  let promise: PromiseLike<any> | undefined;

  return {
    then: (onFulfilled, onRejected) => {
      if (promise == null) {
        promise = asyncFunc();
      }

      return promise.then(onFulfilled, onRejected);
    },
  };
}