Type error when following Next.js guide

[mtilda]

Bug Description

While following this guide, I am getting this type error:

Type error: Cannot assign to 'current' because it is a read-only property.

  26 |     const storeRef = useRef<CounterStoreApi>(null);
  27 |     if (!storeRef.current) {
> 28 |         storeRef.current = createCounterStore();
     |                  ^
  29 |     }
  30 |
  31 |     return (

The error is resolvable by explicitly making the type argument to useRef nullable, like this:

  const storeRef = useRef<CounterStoreApi | null>(null);

Reproduction Link

https://codesandbox.io/p/sandbox/mre-typeerror-when-following-zustands-next-js-guide-2mn5x2

[dbritto-dev]

@mtilda seems is your config -> https://tsplay.dev/w2yzbW. btw, you could try changing this if (!storeRef.current) to if (storeRef.current == null)

[mtilda]

Do you know what about my config caused the error?

[dbritto-dev]

@mtilda could be related to -> https://www.typescriptlang.org/tsconfig/#exactOptionalPropertyTypes.