To follow up on my earlier comment, the KDE platform includes a component model called KParts that, to use modern lingo, is used to perform various "application

To follow up on my earlier comment, the KDE platform includes a component model called KParts that, to use modern lingo, is used to perform various "application mashups", including embedding the Kate editor (comparable to TextMate/BBEdit or UltraEdit/Notepad+, including powerful plugin and scripting APIs) into KDevelop while preserving all of its functionality. KParts allow developers to control how the merguing of things like action and shortcut collections, menus, toolbars etc. is done.