Re: [boost] Painting a bikeshed ...

Subject: Re: [boost] Painting a bikeshed ...
From: Roland Bock (rbock_at_[hidden])
Date: 2015-10-01 10:50:58

On 2015-10-01 16:24, Marshall Clow wrote:
> In Sean Parent's CppCon keynote last week, he went through the process of
> implementing an algorithm he called "sort_subrange", which takes four
> iterators describing two ranges, one a subset of the other, and sorts the
> subrange - as if you had sorted the entire range.  (See
> https://www.youtube.com/watch?v=sWgDk-o-6ZE, starting at about 31:30).
>
> I have implemented this in Boost.Algorithm (crediting Sean) - called
> partition_sort.
>
> However, while I was doing this, I thought of a different algorithm; one
> that gathered all the elements into the subrange as if the entire range was
> sorted, but didn't actually do the sorting.
>
> I've implemented that one, too - but I'm having a bit of trouble coming up
> with a name.
>
> I've used "partition_subrange", but that not that clear.
> Sean has suggested "elements_in_subrange" and "elements_within_subrange".
>
> Here's the declaration:
>
>   template<typename Iterator, typename Pred>
>   void partition_subrange (
>   Iterator first,     Iterator last,
>   Iterator sub_first, Iterator sub_last,
>   Pred p)
>
> /// \brief Gather the elements of the subrange [sub_first, sub_last) that
> is
> ///     inside the range [first, last) as if you had sorted the entire
> range.
>
> Any suggestions?

Assuming that the elements in [first, sub_first) are also less or equal
to the element at sub_first, this is quite similar to nth_element, isn't
it? Then you could call it

mth_to_nth_element

Not too smooth, but it should be clear to anyone who knows about
nth_element.

Best,

Roland