Custom swap function?

Hello,

It will be great if these algorithms allow setting a custom swap function.
In my use-case besides swapping the values I need to do other work (on my qt application I need to fire also signals).

The issue names no files, tests, or specific algorithms. Start by reviewing the sort algorithms and their current swap behavior, then determine which APIs would need a configurable swap operation. Done means the requested custom swap behavior is supported for the relevant algorithms and is covered by tests, including the stated signal-emitting use case.

Written by the indexing model from the issue text.