I would go further in this request and ask for a side view with the counterpart. Xcode for Mac has this feature and it is very useful. Every time I select a .cpp, the header of that file automatically shows up on the side view.
Thanks for the great editor. I've been looking for a lightweight replacement for XCODE, but was unable to find, until, a month ago I googled for "what is the best code editor for Mac" and I found your editor. This app is a masterpiece. Thanks a lot.