How to human-join an array in JavaScript

CopyjoinSentence = (array) ->
  if array.length > 1
    array[0..-2].join(', ') + ', and ' + array[-1..]
  else
    array.join ', '

Copy> joinSentence(['cats', 'dogs', 'pandas'])
# => 'cats, dogs, and pandas'

Copyfunction joinSentence(array) {
  if (array.length > 1) {
    return array.slice(0, -1).join(', ') + ', and ' + array.slice(-1);
  } else {
    return array.join(', ');
  }
};