Re: Draft Node: Fill in the Blank

Neil,

I agree that the "evaluator" function of the children is probably criticizable from the aspect of copy-and-paste (note: in a perfect world that doesn't sniff like Maple or Mathematica does, pasting MathML would actually be inoperable, unless the students have a way to change the flavour of their clipboards!).

The discussion with Paul, however, went into needing several children different from the evaluator:

- a markup that indicates the blank somehow  (the prompt)
- a prefilled formula in some cases (e.g. an answer to be revised) (the default value)
- a formula that is only there to make sure that the blank is big enough (the phantom)

I believe the proposal with the class attribute is only at problem if there is the need for several children and now I am realizing that this appears natural. I sure agree I have no excuse to have not said this before!

paul


Le 9 juil. 2012 à 21:10, Neil Soiffer a écrit :

> 
> > What did you mean by "in-browser comparison"?
> 
> If we allow several expressions associated to a blank then it also makes sense to allow one that allows the recipient user-agent (e.g. a web-page with some javascript) to compare the user-input with the one (given some flexibility).
> 
> My concern now is whether it is good to allow multiple children. From this discussion it sounds unavoidable. And if we do so, how do we markup so that renderers that are unaware of this note still render something partially useful?
> 
> Paul
> 
> 
> I think a significant number of sites that use MathML for evaluation would not consider sending the answers along with the problem as a reasonable solution.  There are many ways to hide the answer from being viewed in the user's browser (CSS, or XML-annotation are two people mentioned already), but users can view the source and copy/paste the MathML into one of many editors to see the answer.  So those solutions are easily defeated and probably not acceptable.
> 
> If you do want to do that, there is no reason you can't wrap the proposed solution (class="MathML-Blank") inside of a semantics element and use annotation-xml for anwsers as you proposed for the answers.  I'm not recommending that for the reasons above.
> 
>     Neil
>