I hate to taint this, but reading up on Fern I have to point to JavaFX. It rings a lot of similarity with what is being talked about here. There may be other frameworks also.
But JFX captures much of this. It doesn't have your schemas (its obviously based on Javas class and object system), but it does have constraints, it does have bindings (not as sophisticated as yours, but they exist and quite useful in practice). It has the scene graph, it handles contextual styling via CSS. It has its layout components, and GUI components. It even has 3D ;).
I will say about the bindings that when the graph gets large it can be fun to try to keep in your head, and, unfortunately, there's no real way to visualize it. So, when something changes (or changes in a way you don't like), it can be an endeavor to source the change and navigate the relationships.
The primary reason I mention this is just to lift it up as an example of many of the concepts you're discussing, but in "production" code, used by many, for quite some time. There may be insights there that can be mined as to possibly decisions that were made that you could apply (or not) to your work. Are the limitations of JFX done by design? Limited by Java? Limited by performance? Limited by "haven't got to it yet"? I don't know, but, anyway, just something you may want to study a little.
I can't stress enough how important and helpful prototype OO has been to the current design. I couldn't imagine doing what I want to do without it. For example, some of the concepts such as configurations and contexts rely on dynamic inheritence.
> There may be insights there that can be mined as to possibly decisions that were made that you could apply (or not) to your work. Are the limitations of JFX done by design? Limited by Java? Limited by performance? Limited by "haven't got to it yet"? I don't know, but, anyway, just something you may want to study a little.
But JFX captures much of this. It doesn't have your schemas (its obviously based on Javas class and object system), but it does have constraints, it does have bindings (not as sophisticated as yours, but they exist and quite useful in practice). It has the scene graph, it handles contextual styling via CSS. It has its layout components, and GUI components. It even has 3D ;).
I will say about the bindings that when the graph gets large it can be fun to try to keep in your head, and, unfortunately, there's no real way to visualize it. So, when something changes (or changes in a way you don't like), it can be an endeavor to source the change and navigate the relationships.
The primary reason I mention this is just to lift it up as an example of many of the concepts you're discussing, but in "production" code, used by many, for quite some time. There may be insights there that can be mined as to possibly decisions that were made that you could apply (or not) to your work. Are the limitations of JFX done by design? Limited by Java? Limited by performance? Limited by "haven't got to it yet"? I don't know, but, anyway, just something you may want to study a little.
I wish you luck on your project!