$diff(<word list 1> / <word list 2>)

• There must be a literal slash character ('/') that separates the two word lists. If it is omitted the empty string is returned.
• It is not required to have spaces on either side of the slash, but it also does not hurt to have them.
• The return value is a word list comprised of the negated set-difference of <word list 1> and <word list 2>, that is to say:
• The return value is a word list of all words that are in ONE BUT NOT BOTH of the word lists.
• All extra whitespace around words will be lost.
• Double quoted words are honored, but the double quotes will be lost in the return value.

Use this function if you need to find the un-common elements of two different word lists.

All words that are in either <word list 1> or <word list 2> but not both.

$diff(one two three / two three four)     returns "one four"
$diff(one two / three four)               returns "one two three four"