docs: function flattenDownDepth (array, result, depth) {
    depth--
  
    for (var i = 0; i < array.length; i++) {
      var value = array[i]
  
      if (depth > -1 && Array.isArray(value)) {
        flattenDownDepth(value, result, depth)
      } else {
        result.push(value)
      }
    }
  
    return result
  }