I understand that judging the success of an evaluation may not be feasible. For now it would help me to register when a cell is evaluated, but I could imagine other useful infos for the future.
For a possible form of the interface - I like that of CodeMirror:
When CM is a CoceMirror node,
- I can add a Handler for an Event by calling CM.addEventListener(Event,Handler) and
- I can call a Method of the CodeMirror API by CM.CodeMirror.Method()
Similarly, for a SageCell node
SC one might call
SC.addEventListener('isEvaluated',Handler) and something like
SC.SageCellIInput.Method() where
Method is a CodeMirror method passed through to SageCell's CodeMirror.
Later one might add further methods, also to access the output of a SageCell in a similar way, if needed.
Background: I am experimenting with a Vue app that creates SageCells dynamically and I'd be ready to share the Vue component that builds the SageCell as a Github gist. For this component I'd prefer, if I could make its methods independent of the current internal structure of SageCells.