Sorting algorithm

[Xinok]

On 10/8/2011 9:15 AM, Andrei Alexandrescu wrote:
> On 10/07/11 23:00, Xinok wrote:
>> Thanks, I'll look into it when I have a little more time.
>
> Looking forward to it.
>
>> If my algorithm were to be implemented in Phobos, the template arguments
>> for std.algorithm.sort would need to be modified. For my algorithm to be
>> stable, it requires defining two conditions, both a 'less' and 'greater'.
>
> Wouldn't swapping the argument to less work?
>
>
> Andrei

The merge step in my algorithm is similar to Timsort, in that it can 
merge left to right as well as right to left. This needs two conditions 
to do a stable sort, 'less or equal' and 'greater or equal'.

By swapping the arguments, you can only get 'greater or equal'. You're 
still missing 'less or equal', which is required for my algorithm to be 
stable.

It wouldn't be difficult to overload the template. When using an 
unstable sort, the greater argument can be left empty.
sort!("a < b")
would simply translate to:
sort!("a < b", "", SwapStrategy.unstable)