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const App = () => {
  const [showModal, setShowModal] = useState(false);
  const handleKeyup = e => e.keyCode === 27 && setShowModal(false);
  const toggleModal = () => setShowModal(!showModal);
  useEffect(() => {
    if (showModal) window.addEventListener('keyup', handleKeyup);
    return () => window.removeEventListener('keyup', handleKeyup);
  });
  
  return <div onClick={toggleModal} className="App">

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const Modal = ({children}) => <div className='Modal'>
    {children}
</div>;

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function factorial(n) {
  if (n <= 1) return 1;
  return n * factorial(n - 1);
}

console.log(factorial(5)); // 120

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function recursiveFn(n) {
  if (n < 0) return true;
  recursiveFn(n - 1);
}

recursiveFn(100000); // RangeError: Maximum call stack size exceeded

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function traverseDOM(tree) {
  if (isLeaf(tree)) tree.className = 'leaf';
  else for (const leaf of tree.childNodes) traverseDOM(leaf);
}

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function trampoline(f) {
  return function trampolined(...args) {
    let result = f.bind(null, ...args);

    while (typeof result === 'function') result = result();

    return result;
  };
}

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const factorial = trampoline(function _factorial(n, acc = 1) {
  if (n <= 1) return acc;
  return () => _factorial(n - 1, n * acc);
});

console.log(factorial(5));

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const recursiveFn = trampoline(function _recursiveFn(n) {
  if (n < 0) return;
  return () => _recursiveFn(n - 1);
});

recursiveFn(100000);
console.log('No range error!');

baranovxyz

interface ColumnOfStrings {
  _id: string; // MongoDB id field
  type: 'string'; // yes, it is literal 'string' for column of strings
  values: (string | null)[]; // an array, each element is either string or null
}

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function compress(column) {
  column.compression = 'ZIP_JSON_STRINGIFY';
  column.values = zip(JSON.stringify(column.values));
  return column;
}