Yes, that was my first thought too. The concept is similar.
Get rid if the source-files and put every function/method in its own "editor". However, as far as I remember navigation to/from callers was not possible in Smalltalk.
You don't have to get rid of files; while the Smalltalk image was great and offer some advantages, there has been Smalltalks that worked on files and Lisp showed that you can have still have a working image with files.
> navigation to/from callers was not possible in Smalltalk
You can navigate implementations and references to symbols, which mostly work like how unannotated dynamic languages (like Ruby, Python) would work.
There would be false positives; but it isn't as bad as it sounds unless you look up common symbols like `#value` and `#value:`.
In some Smalltalk environments and some extensions, you could narrow them by scope, like look up references to this symbol within that package. I think Dolphin did that.
Get rid if the source-files and put every function/method in its own "editor". However, as far as I remember navigation to/from callers was not possible in Smalltalk.