ts2322

A moment ago I got an error that reads like this:

Type '(() => void) | null' is not assignable to type '() => void | null'. ts2322

I was really confused for a moment. Then I realized (() => void) | null means: Either a) a function that neither takes any argument nor returns any value; or b) null.

And () => void | null means a function that does not take any argument. And there are two possibilities when this function returns: Either it doesn't return anything or it returns a null.

Here's blog post explaining why the void keyword is useful while devving.

And I mostly agree with this blog post.