** Using WeBWorK **

The reason for this difference is that {1,2} is a single set whereas x=1 or x=2 is treated as the union {1} U {2}, and the error messages for unions are different from those for sets (because unions can contain intervals, not just numbers).

I have updated things so that x=1 or x=2 will form a set rather than a union, so the messages should now be more like what you expect (when you have showHints=>1 specified). I've also added error messages for things like x=1 or x=1 where the student has entered redundant answers.

To get this, you will need to update your copies of:

pg/lib/Value/AnswerCheckers.pm,
pg/lib/Value/Set.pm and
pg/macros/contextInequalities.pl.

Let me know if this doesn't do what you want.

Davide