Complexity nomenclature

[Tofu Ninja via Digitalmars-d]

On Friday, 4 December 2015 at 03:37:10 UTC, Andrei Alexandrescu 
wrote:
> On 12/3/15 10:29 PM, Jack Stouffer wrote:
>> On Friday, 4 December 2015 at 02:21:12 UTC, Andrei 
>> Alexandrescu wrote:
>>> On 12/03/2015 09:10 PM, Idan Arye wrote:
>>>> The complexities of the operations is a property of the data 
>>>> structure
>>>> being used. If each collection type will have it's own set 
>>>> of method
>>>> names based on the complexity of operations on it, we won't 
>>>> be able to
>>>> have templated functions that operate on any kind of 
>>>> collection(or at
>>>> the very least, these functions will be really tedious to 
>>>> code).
>>>
>>> Your premise is right but you reach the negation of the 
>>> correct
>>> conclusion. -- Andrei
>>
>> How so? If a singly linked list and a doubly linked list have 
>> two
>> different method names for the same operation, then they 
>> cannot be
>> easily templated.
>
> Took me a while to figure. There's a hierarchy of operations, 
> e.g. if a collection implements insert, it automatically 
> implements linearInsert. And so on. The collections framework 
> provides these defaults, so client code that needs quick insert 
> uses insert, whereas code that's fine with a linear upper bound 
> uses linearInsert and captures both.
>
> Another way to look at it: in STL container-independent code is 
> near impossible because different containers use the same 
> signature for operations that are different (either wrt 
> iterator invalidation or complexity). My design avoids that by 
> giving distinct operations distinct names.
>
>
> Andrei

This sounds really complicated to use? What are the benefits?
When would a generic algorithm even need to know the complexity 
of the container?

Also maybe a simpler idea would just be to annotate the the 
operations with there complexity with UDAs. That way things that 
really care about the complexity can get it, and those who don't 
can ignore it. It has the benefit of being self documenting as 
well.