[Python-ideas] Uniquify attribute for lists

[Michael Foord]

On 16 November 2012 12:39, Paul Moore <p.f.moore at gmail.com> wrote:

> On 16 November 2012 12:28, Robrecht De Rouck <de.rouck.robrecht at gmail.com>wrote:
>
>> Hello,
>>
>> I just wanted to bring to your attention that an *attribute for removing
>> duplicate elements* for lists would be a nice feature.
>>
>> *def uniquify(lis):
>>     seen = set()
>>     seen_add = seen.add
>>     return [ x for x in lis if x not in seen and not seen_add(x)]*
>> *
>> *
>> The code is from this post<http://stackoverflow.com/questions/480214/how-do-you-remove-duplicates-from-a-list-in-python-whilst-preserving-order>. Also
>> check out this performance comparison<http://www.peterbe.com/plog/uniqifiers-benchmark> of
>> uniquifying snippets.
>> It would be useful to have a uniquify attribute for containers in
>> general.
>>
>
>
> list(set(ls))
>

This loses order. Both solutions suffer from the problem that they only
work with hashable objects.

Michael


>
> Paul
>
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