The "problem" with this is insisting on a free-text-editable version of "the code", which makes everything much harder than it needs to be. A better approach i

The "problem" with this is insisting on a free-text-editable version of "the code", which makes everything much harder than it needs to be. A better approach is to go the other way, i.e. maintain the AST and project it in an editable fashion, whether that be in a graphical sense, textually, etc. This lets you constrain the edit gestures to things that are valid in the context of the AST, and avoids the problem where the user has typed a bunch of gibberish and you can no longer "back convert" to some other representation. A really good (but sadly largely abandoned) example of this is https://mbeddr.com https://mbeddr.com