instance method Array#uniq
Array#uniq([sorted = false]) → Array
Boolean) – Whether the array has already been sorted. If
true, a less-costly algorithm will be used.
Produces a duplicate-free version of an array. If no duplicates are found, the original array is returned.
On large arrays when
false, this method has a potentially
large performance cost.
[1, 3, 2, 1].uniq(); // -> [1, 2, 3] ['A', 'a'].uniq(); // -> ['A', 'a'] (because String comparison is case-sensitive)