Thanks for the answers.  I did in fact know about \incrementnumber, but I couldn't find any information about the counter.  Where would I find such information, aside from asking on this mailgroup?

As for identifying each question and referring to it: that is an excellent solution, but in fact I have only rarely to leave out an answer, and the small amount of bookkeeping required is not at all onerous.

Thanks again,
Alasdair

On Wed, Feb 15, 2012 at 3:27 AM, Thomas A. Schmitz <thomas.schmitz@uni-bonn.de> wrote:
On 2/14/12 1:48 PM, Hans Hagen wrote:
\starttext
\startitemize[n]
\item First question
\phantom{\item }
\item Third question
\phantom{\item }
\item Fifth question
\item Sixth question
\stopitemize
\stoptext

or something

\starttext
\startitemize[n]
\item First question
\incrementnumber[itemgroup:itemize]
\item Third question
\incrementnumber[itemgroup:itemize]
\item Fifth question
\item Sixth question
\stopitemize
\stoptext

Just a hint: however you do it, I think this is not the best approach. you write:

I'm typing out solutions to questions in some student notes, and the
missing item is a question for which a written solution is not necessary.


If this is a recurrent task, i.e. if you regularly make up student problems and then typeset the solutions, this approach is inefficient because you're doing the book keeping yourself. If, for example, you decide to delete one of the questions without written solution, you will have to delete the \incrementnumber as well. It may be better if you let ConTeXt do the book keeping: give every question a unique identitfier like so

\startitem[p:1:2]
 Problem?
\stopitem

and then typeset the solutions by referring back to this identifier:

\sym{\in[p:1:2]}

That way, the numbers in problems and solutions will always be correct, even if you rearrange etc. (I often typeset such exercise stylesheets, and after many years, that's my approach today.)

Thomas

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