irregular = (length = 10, randomness = 1) => {
  const values = [0];
  const total = length - 1;
  for (let i = 1; i < total; i++) {
    const previousValue = values[i - 1];
    const spacing = i / total;
    const segmentEnd = (i + 1) / total;
    const randomVariation = spacing + (segmentEnd - spacing) * Math.random();
    // Mix the even spacing and random variation based on the randomness parameter
    const randomValue = spacing * (1 - randomness) + randomVariation * randomness;
    values.push(clamp(randomValue, previousValue, 1));
  }
  values.push(1);
  return linear(...values);
}
Generate random steps
@param  {Number} [length] - The number of steps
@param  {Number} [randomness] - How strong the randomness is
@return {EasingFunction}