I am working on a project to use WeBWorK to do simple automatic proof-checking. (A non-WeBWorK demo in JavaScript is hereĀ http://curtisfenner.github.io/Proof-Drilling/ )

The general strategy is to

- read student input as statements
- parse statements, compare structure of statements against axioms
- respond with success / errors

I have several troubles getting this to work in WeBWorK, so if someone could point me to examples that solve these problems, that would be great!

- In an answer-checker, is it possible to read the structure of a student answer, instead of just evaluating it?
- The Formula MathObject looks promising, but I could not figure out how to make, e.g., MultiAnswer give me the student answer as Formulas.

- How do I add custom operators?
- I had only very limited success when trying different examples on the Wiki. Are there full examples of completely new operators being added to a context?

Thank you!