#FreeCodeCamp Bonfire: Truncate a string

function truncate(str, num) {
  if (num < str.length) {
    sliced = str.slice(0, num-3);
    var truncated = sliced + "...";
    return truncated;
  }
  else { return str; }
}

truncate("A-tisket a-tasket A green and yellow basket", 11, "");