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@toolpad/utils

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Shared utilities used by Toolpad packages.

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.default = useDebouncedHandler; var React = _interopRequireWildcard(require("react")); function _getRequireWildcardCache(e) { if ("function" != typeof WeakMap) return null; var r = new WeakMap(), t = new WeakMap(); return (_getRequireWildcardCache = function (e) { return e ? t : r; })(e); } function _interopRequireWildcard(e, r) { if (!r && e && e.__esModule) return e; if (null === e || "object" != typeof e && "function" != typeof e) return { default: e }; var t = _getRequireWildcardCache(r); if (t && t.has(e)) return t.get(e); var n = { __proto__: null }, a = Object.defineProperty && Object.getOwnPropertyDescriptor; for (var u in e) if ("default" !== u && {}.hasOwnProperty.call(e, u)) { var i = a ? Object.getOwnPropertyDescriptor(e, u) : null; i && (i.get || i.set) ? Object.defineProperty(n, u, i) : n[u] = e[u]; } return n.default = e, t && t.set(e, n), n; } function defer(fn, params, delay) { const timeout = setTimeout(() => { fn.current(...params); }, delay); return { startTime: Date.now(), timeout, params }; } /** * Creates a debounced version of the handler that is passed. The invocation of [fn] is * delayed for [delay] milliseconds from the last invocation of the debounced function. * * This implementation adds on the lodash implementation in that it handles updates to the * delay value. */ function useDebouncedHandler(fn, delay) { const fnRef = React.useRef(fn); React.useEffect(() => { fnRef.current = fn; }, [fn]); const delayedInvocation = React.useRef(null); const clearCurrent = React.useCallback(() => { if (delayedInvocation.current) { clearTimeout(delayedInvocation.current.timeout); delayedInvocation.current = null; } }, []); React.useEffect(() => { if (!delayedInvocation.current) { return; } const { startTime, params } = delayedInvocation.current; const elapsed = Date.now() - startTime; const newDelay = Math.max(delay - elapsed, 0); clearCurrent(); delayedInvocation.current = defer(fnRef, params, newDelay); }, [delay, clearCurrent]); return React.useCallback((...params) => { clearCurrent(); delayedInvocation.current = defer(fnRef, params, delay); }, [delay, clearCurrent]); }