Memoized values with empty inputs array are known to be static

[yuchi]

In the following example the value of values should never change, and we should be able to treat it as static:

const values = React.useMemo(() => new Array(12), []);

I say “should” because the official React documentation states:

You may rely on useMemo as a performance optimization, not as a semantic guarantee. In the future, React may choose to “forget” some previously memoized values and recalculate them on next render, e.g. to free memory for offscreen components. Write your code so that it still works without useMemo — and then add it to optimize performance.

We will skip this optimization since we cannot guarantee the semantic correctness in the long run.