[Python-ideas] list…pushed, or something

[MRAB]

On 28/03/2013 05:28, Bruce Leban wrote:
>
> On Wed, Mar 27, 2013 at 10:11 PM, Shane Green <shane at umbrellacode.com
> <mailto:shane at umbrellacode.com>> wrote:
>
>     [seen.added(value) for value in sequence if value not in seen]  *
>
>
> Here's an easy way to do it:
>
>  >>> seen = set()
>  >>> seq = [3,2,1,2,3,4,5,4]
>  >>> [seen.add(v) or v for v in seq if v not in seen]
> [3, 2, 1, 4, 5]
>  >>> seen
> {1, 2, 3, 4, 5}
>
I think I would prefer a "unique" function that yields unique items:

def unique(items):
     seen = set()

     for item in items:
         if item not in seen:
             seen.add(item)
             yield item

 >>> seq = [3,2,1,2,3,4,5,4]
 >>> list(unique(seq))
[3, 2, 1, 4, 5]