Request for feedback on Signature Assistant

[David Nolden]

IMO the signature-assistant has one big conceptual problem: It always
rewrites the whole function declaration line. Since in C++ there is
many redundant ways how to write type-names, this will always cause
problems.

I think the right way to work would be remembering a sequence of
edits, like for example:
- Replace 1st argument with ...
- Remove 3rd argument
- Remove 4th argument

And then replaying those changes on the other side. That way, we would
overwrite only those parts that were actually changed, and we might
also solve matching-problems in places where the argument-declaration
names don't match properly etc.

Greetings, David