mutable_refs.jsx

const { useEffect, useRef } = require("react");

const noop = () => {};

class Editor {
    constructor(element) {
        this.element = element;
    }

    destroy() {
        // ...
    }
}

const useEditor = (containerRef) => {
    const editorRef = useRef(null);
    useEffect(() => {
        if (!containerRef.current) {
            return noop;
        }

        const editor = new Editor(containerRef);
        editorRef.current = editor;

        return () => {
            editorRef.current.destroy();
            editorRef.current = null;
        };
    }, [containerRef]);

    return editorRef;
}