CoffeeScript removes the same elements from the array

Remove the same elements from the array

Problem

You want to remove the same element from the array.

Solution

Array::unique = ->
  output = {}
  output[@[key]] = @[key] for key in [0...@length]
  value for key, value of output

[1,1,2,2,2,3,4,5,6,6,6,"a","a","b","d","b","c"].unique()
# => [ 1, 2, 3, 4, 5, 6, 'a', 'b', 'd', 'c' ]

Discuss

There are many unique ways to do this in JavaScript. This time it's based on "the fastest way to find the only element of an array" from here.

Note: Extending a local object is generally considered a bad practice in JavaScript, even though it is fairly common in ruby languages (Reference: Maintainable JavaScript: Don't modify objects you don't't own.)