> Otared Kavian <mailto:otared@gmail.com>
> 6. November 2016 um 11:43
> Hi Wolfgang,
>
> Thanks for the solution you sent yesterday.
> Your solutions solves the problem I was fighting with, but when I try 
> to apply it to my real document there is an issue when some questions 
> don’t have answers. This prevents the synchronization of Questions and 
> Answers if one doesn't issue the commands
> \beginanswer
> \incrementcounter[answer]
> \endanswer
>
> right after a question without an answer. And when the above commands 
> are issued, the last Question does not show the link to its 
> corresponding Answer.
>
> Below is your modified example where one can see the problem (please 
> see the fifth Question in the source below).
>
> Best regards: OK
> %%%% begin example-ws.tex
>
> \setupinteraction[state=start]
>
> \newcounter\QuestionCounter
> \newcounter\AnswerCounter
>
> \define[1]\QuestionTextCommand
>   {\doglobal\increment\QuestionCounter
>    \pagereference[question:\QuestionCounter]%
>    \doifreferencefoundelse{answer:\QuestionCounter}
>      {\goto{#1}[answer:\QuestionCounter]}
>      {#1}}
>
> \define[1]\AnswerTextCommand
>   {\doglobal\increment\AnswerCounter
>    \pagereference[answer:\AnswerCounter]%
>    \doifreferencefoundelse{question:\AnswerCounter}
>      {\goto{#1}[question:\AnswerCounter]}
>      {#1}}
Add a check for triatypesetting mode to increment \QuestionCounter
only once for each question.

\define[1]\QuestionTextCommand
   {\doifnotmode{*trialtypesetting}
      {\doglobal\increment\QuestionCounter
       \pagereference[question:\QuestionCounter]}%
    \doifreferencefoundelse{answer:\QuestionCounter}
      {\goto{#1}[answer:\QuestionCounter]}
      {#1}}

\define[1]\AnswerTextCommand
   {\doifnotmode{*trialtypesetting}
      {\doglobal\increment\AnswerCounter
       \pagereference[answer:\AnswerCounter]}%
    \doifreferencefoundelse{question:\AnswerCounter}
      {\goto{#1}[question:\AnswerCounter]}
      {#1}}
> %% Why this command generates an erreor?
> \define\noanswer{%
> \beginanswer
> \incrementcounter[answer]
> \endanswer}
The block environment can’t be used within a definition but
you put the content in a bufer and call then the buffer content
with your \noanswer command.

\startbuffer[noanswer]
     \beginanswer
     \doglobal\increment\AnswerCounter
     \incrementcounter[answer]
     \endanswer
\stopbuffer

\define\noanswer
   {\getbuffer[noanswer]}

Wolfgang