shelving/react/useInstance.js

Toolkit for using data in JavaScript.

import { isArrayEqual } from "../util/equal.js";
import { useProps } from "./useProps.js";
/**
 * Use a memoised class instance.
 * - Creates a new instance of `Constructor` using `args`
 * - Returns same instance for as long as `args` is equal to previous `args`.
 */
export function useInstance(Constructor, ...args) {
    const internals = useProps();
    // Update `internals` if `args` changes or `instance` is not set.
    if (!internals.args || !internals.instance || !isArrayEqual(args, internals.args)) {
        internals.instance = new Constructor(...args);
        internals.args = args;
    }
    return internals.instance;
}