Issue 1323

[Pelle]

On 01/09/2011 03:07 AM, Robert Clipsham wrote:
> On 08/01/11 23:20, bearophile wrote:
>> Andrei has recently closed issue 1323, it's a small but very useful
>> feature, so I suggest some public discussion:
>> http://d.puremagic.com/issues/show_bug.cgi?id=1323
>>
>> Lines like this is present thousands of time in my Python code:
>> n in [1, 2, 3]
>> c in "hello"
>> "llo" in some_string
>>
>> Bye,
>> bearophile
>
> I'd be all for this, except it's inconsistent.
> ----
> auto arr = [ "foo" : 1, "bar" : 2 ];
> assert("foo" in arr);
> ----
> in for associative arrays works by key, if it works by value for normal
> arrays it's inconsistent, and if it works for keys people will wonder
> why it's not working as expected.

No, people will not wonder about that. See also: python. Seriously 
people, stop giving this as a reason.

A much better argument is the in operator should run in O(log n) for 
anything, meaning it won't work for a general unsorted array.

I suggest going for (v in assumeSorted(arr)) or (arr.contains(v)), where 
contains is the canFind function blessed with a new, superior name. :-)