Canon Cat did not have graphical capabilities at the time, but its successor the Archy prototype had them. Instead of being mouse-centric like the Mac/Lisa, it

Canon Cat did not have graphical capabilities at the time, but its successor the Archy prototype had them. Instead of being mouse-centric like the Mac/Lisa, it was intended to handle graphical objects mostly or entirely by keyboard (like Emacs, but without modes), and Raskin had plans to make it work like an infinitely zoomable browser. The think with Archy is that it contained all the power of a command line for chaining commands, but it also worked on documents, all with a very well thought out interaction model that's easy to learn (in contrast with Emacs, which offers the same power but it's a nightmare to learn). Yeah, a low-level "graph editor" extensible library that could be plugged-in anywhere to provide a common interaction, that would be great. Things like tree widgets provide some of that, but of course they only support a specific subset of graphs.