http://www.freecodecamp.com/kkas 's solution for Bonfire: Truncate a string

bonfire-truncate-a-string.js

// Bonfire: Truncate a string
// Author: @kkas
// Challenge: http://www.freecodecamp.com/challenges/bonfire-truncate-a-string
// Learn to Code at Free Code Camp (www.freecodecamp.com)

function truncate(str, num) {
  // Clear out that junk in your trunk
  var len = num > 3 ? num - 3 : num;
  
  return str.length > num ? str.slice(0, len) + "..." : str;
}

//truncate("A-tisket a-tasket A green and yellow basket", 11);
//truncate("A-tisket a-tasket A green and yellow basket", "A-tisket a-tasket A green and yellow basket".length);
truncate("A-", 1);