@restart/hooks/cjs/useRefWithInitialValueFactory.js

"use strict";

exports.__esModule = true;
exports.default = useRefWithInitialValueFactory;
var _react = require("react");
const dft = Symbol('default value sigil');

/**
 * Exactly the same as `useRef` except that the initial value is set via a
 * factory function. Useful when the default is relatively costly to construct.
 *
 *  ```ts
 *  const ref = useRefWithInitialValueFactory<ExpensiveValue>(() => constructExpensiveValue())
 *
 *  ```
 *
 * @param initialValueFactory A factory function returning the ref's default value
 * @category refs
 */
function useRefWithInitialValueFactory(initialValueFactory) {
  const ref = (0, _react.useRef)(dft);
  if (ref.current === dft) {
    ref.current = initialValueFactory();
  }
  return ref;
}