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

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2022-04-25 02:47:15 +00:00
"use strict";
exports.__esModule = true;
exports.default = void 0;
var _react = require("react");
/**
* Runs an effect only when the dependencies have changed, skipping the
* initial "on mount" run. Caution, if the dependency list never changes,
* the effect is **never run**
*
* ```ts
* const ref = useRef<HTMLInput>(null);
*
* // focuses an element only if the focus changes, and not on mount
* useUpdateEffect(() => {
* const element = ref.current?.children[focusedIdx] as HTMLElement
*
* element?.focus()
*
* }, [focusedIndex])
* ```
* @param effect An effect to run on mount
*
* @category effects
*/
function useUpdateEffect(fn, deps) {
var isFirst = (0, _react.useRef)(true);
(0, _react.useEffect)(function () {
if (isFirst.current) {
isFirst.current = false;
return;
}
return fn();
}, deps);
}
var _default = useUpdateEffect;
exports.default = _default;