GoScrobble/web/node_modules/@restart/hooks/cjs/useRefWithInitialValueFactory.js

30 lines
742 B
JavaScript

"use strict";
exports.__esModule = true;
exports.default = useRefWithInitialValueFactory;
var _react = require("react");
var dft = Symbol('default value sigil');
/**
* Exactly the same as `useRef` except that the initial value is set via a
* factroy 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) {
var ref = (0, _react.useRef)(dft);
if (ref.current === dft) {
ref.current = initialValueFactory();
}
return ref;
}