To take a diff for example, not only do you need to illustrate the diff version of (I drew a new line from here to here and made this other box green), you would also need to illustrate patches to textual details and how they related to the graphical code.

Maybe I can imagine a solution that could do that (at great expense). I cannot imagine the language being friendly enough that third-party compilers, IDEs, or static-analysis tools would be feasible.