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About the implementation of del in Python 3


Le 06/07/2017 ? 09:29, Terry Reedy a ?crit :
> On 7/6/2017 3:08 AM, Dan Wissme wrote:
>> I thought that del L[i] would slide L[i+1:] one place to the left,
>> filling the hole, but :
>>
>>  >>> L
>> [0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100]
>>  >>> id(L)
>> 4321967496
>>  >>> id(L[5])    # address of 50 ?
>> 4297625504
>>  >>> del L[2]
>>  >>> id(L[4])     # new address of 50 ?
>> 4297625504
>>  >>> id(L)
>> 4321967496
>
>> So the element 50 is still at the same memory location.
>> What del L[i] do exactly, and what is its complexity ? O(1) or O(n) ?
>
> A list is an array of references to objects that exist outside of the
> list.  Del deleted a reference, not any of the objects.

So what 'del L[i]' do exactly in memory ? Same as L.pop(i) ? with 
complexity O(n-i) ?

      dan