Heap: container or range?

[Sean Kelly]

Sean Kelly wrote:
> Andrei Alexandrescu wrote:
>>
>> Ah, never mind all that. I realized that I can't have a heap range. 
>> This is because heaps must mutate the underlying range in-place and 
>> any copy will mess the heap up. Here's the example that clarify it for 
>> me:
>>
>>         int[] a = [ 4, 1, 3, 2, 16, 9, 10, 14, 8, 7 ];
>>         auto h = Heap!(int[])(a);
>>         assert(equal(take(5, h) == [ 8, 9, 10, 14, 16 ]);
>>
>> At this point the mutations done by take messed up h already!!
> 
> Hm... so assuming this is a min heap, I have:
> 
> a = [4,1,3,2,16,9,10,14,8,7];
> h = [1,2,3,4,7,9,10,14,8,16];
> take(5, h);
> h = [8,10,9,16,14];
> 
> Shouldn't take call next repeatedly on the heap, which will in turn 
> perform a popHeap operation?  It's difficult to be sure what the result 
> will be after take(5,h) occurs, but it should still be a valid heap, 
> correct?

Oh, I would also expect:

a = [8,10,9,16,14, garbage];

Since it isn't aware of the length adjustment.  Perhaps this is what you 
meant?


Sean