[WWdevel] Filtering of characters in student answers

[Davide P.C. <dp...@un...>]

Folks:

Most of the routines that build answer boxes filter the student  
answers so that the text they produce can be passed through EV3.   
This is because the result of something like ans_rule(10) includes  
the previous answer, when available, as part of its text, and if the  
ans_rule() occurs within BEGIN_TEXT/END_TEXT, then that text will be  
passed to EV3() for further processing.  This means that if the  
student answer included something like \(...\), then it would be  
processed as mathematics, producing garbage in the answer blank for  
the student.

The current solution is to remove characters like \, @, $ and ` from  
the student's answer to prevent further processing, but I think there  
is a better solution.  If these characters were changed to their HTML  
unicode references (\, @, $, and `), then they  
would pass through EV3() unchanged, but would still appear correctly  
in the browser.  This would allow the full preservation of student  
answers.  (I needed something like this for the essay-answer-with- 
preview feature that I was working on, and it does seem to work.)

Comments?

Davide