Not sure if the timsort namespace is a good idea. The namespace name clash is relatively benign. An entity other than namespace could be named timsort and that conflict would not compile... If you decide that such a clash is unlikely, then consider the timsort::sort and timsort::merge names rather than the repetitive timsort::timsort and timsort::timmerge.

To be honest I don't plan to change anything until someone complains that it breaks things in their code base, just letting the issue opened to let people know that we're aware of the potential issue.