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A click handler calls setCount(count + 1) three times. What is count after one click?

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A React component's click handler calls setCount(count + 1) three times in a row, starting from count = 0. What is count after one click? The snippet models React's update queue; it prints the result for that handler and then for the same handler written with setCount(c => c + 1).

1// A simplified model of React's update queue.
2function click(count, makeUpdates) {
3  const queue = [];
4  const setCount = (update) => queue.push(update);
5  makeUpdates(count, setCount);
6  return queue.reduce((s, u) => (typeof u === 'function' ? u(s) : u), count);
7}
8console.log(click(0, (count, set) => { set(count + 1); set(count + 1); set(count + 1); }));
9console.log(click(0, (count, set) => { set((c) => c + 1); set((c) => c + 1); set((c) => c + 1); }));

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One line per console.log. Arrays as [1, 2, 3], objects as { a: 1 }, an uncaught error as Uncaught TypeError: message (Chrome and Node wording).

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