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Dear List, I'm trying to have problem solutions automatically collected, each with its corresponding problem number, e.g. 2.3, and then typeset at the end of a document. Thus, I imagine something like \startproblem{A problem title} % Problem 1.1 A question \startsolution An answer \stopsolution \stopproblem And then the solution(s) would appear at the end (with the "1.1" remembered from when the problem was typeset): Solution to Problem 1.1. An answer It seems that buffers are the way to do this. But I cannot quite get the automatic numbering to work. The delayed evaluation and information passing between lua and ConTeXt has me confused and tangled in a knot. Below is a minimal almost-working example. The issue is in the line {\ctxlua{userdata.addTempToBuffer('#1', [==[\getnumber[problem]]==])}} which ends up putting the verbatim string "\getnumber[problem]" into the temp buffer, rather than the typeset result, which would be something like 1.1 or 1.2. I've read the cld-mkiv.pdf manual, but I must be missing a simple solution to getting ConTeXt to send back the result of \getnumber[problem]. I've also tried the analogous context.getnumber({"problem"}), though without success. Does anyone see what I am missing? Many thanks! -Sanjoy \defineenumeration[problem] [title=yes, text=Problem, way=bychapter, prefix=chapter] \defineenumeration[solution][problem] \setupenumeration [solution][text={Solution to problem}, number=no] \def\test#1{[#1]} % appendbuffer modified from Sietse Brouwer's on mailing list (Jan 15, 2013) \startluacode userdata = userdata or { } function userdata.addTempToBuffer(buffername, problem) buffers.append( buffername, '\\startsolution{' .. problem .. '}\n' .. buffers.getcontent('APPENDTEMP') .. '\n\\stopsolution\n\n' ) end \stopluacode \def\startappendbuffer[#1]% {\def\stopappendbuffer% {\ctxlua{userdata.addTempToBuffer('#1', [==[\getnumber[problem]]==])}} \dostartbuffer[APPENDTEMP][startappendbuffer][stopappendbuffer]} \starttext \chapter{One} \startproblem{Test} Test problem \startappendbuffer[soln] Solution \stopappendbuffer \stopproblem \startproblem{Test} Test problem \startappendbuffer[soln] Solution \stopappendbuffer \stopproblem \typebuffer[soln] \stoptext