Make auto-hiding solutions machinery for exercises

[eteq]

Right now there's not really a way to include the solution to exercises inside the notebook. What would be ideal would be a way to "hide" cells, so that when someone opens up the notebook, they can hack around with it until they're done, and then click a "show solution" button.

There's some notebook add-ons that do this, but I'm not sure anyone fits this exact need. So it might need to be a custom js addon we need to embed in the notebooks...

[adrn]

Maybe something like this: http://jupyter-contrib-nbextensions.readthedocs.io/en/latest/nbextensions/exercise/readme.html

[eteq]

Oh wow, that's exactly what I was thinking of, @adrn.

The question is how to have it be integrated in the notebooks instead of requiring an external extension that needs to be installed. Do you know of any way to embed the relevant bits in the notebooks themselves? Ideally this would include the editing toolbar, but that's not an absolute requirement I suppose.

We'd also need to have the generated pages hide the answers. That's probably easier because if I understand those notebooks correctly, all we'd need to do is set the css to make the exercise divs be display: none.

[kelle]

I actually really like this and would be open to considering it making it a requirement for the notebooks, if technically feasible.