@shopify/polaris/esnext/utilities/use-lazy-ref.js

Shopify’s product component library

import { useRef } from 'react';
const UNIQUE_IDENTIFIER = Symbol('unique_identifier');
/**
 * useLazyRef provides a lazy initial value, similar to lazy
 * initial state the initialValue is the value used during
 * initialization and disregarded after that.
 * @param initialValue - A function that will return the initial
 * value and be disregarded after that
 * @returns MutableRefObject<T> - Returns a ref object with the
 * results from invoking initial value
 */
export function useLazyRef(initialValue) {
    const lazyRef = useRef(UNIQUE_IDENTIFIER);
    if (lazyRef.current === UNIQUE_IDENTIFIER) {
        lazyRef.current = initialValue();
    }
    return lazyRef;
}