mobile typing isn't scored — practice only

function deepClone(value) {

JavaScript · general · type the snippet below to practice

wpm0

acc100%

time–

def fib(n): a, b = 0, 1 for _ in range(n): a, b = b, a + b return a

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about this snippet

This is the deepclone snippet in JavaScript — 10 lines of real JavaScript code that exercises common patterns you'll see in production. DeveloperType scores you on net WPM and accuracy and only counts runs above 95% accuracy on the leaderboard, so practice rewards precision, not speed alone.

view source (10 lines)

function deepClone(value) {
  if (value === null || typeof value !== "object") return value;
  if (Array.isArray(value)) return value.map(deepClone);
  const out = {};
  for (const key of Object.keys(value)) {
    out[key] = deepClone(value[key]);
  }
  return out;
}

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