The following
Code:
sysuse bplong
bayes: mixed bp i.when || patient: , noconstant residuals(exchangeable)
aborts with the following error message:

random effects level patient is empty
an error occurred when bayes executed mixed
r(198);

Does anyone see what I'm doing wrong?

(The code is excerpted; the complete do-file and SMCL log file are attached below.)

The helpfile, help bayes_mixed, specifically mentions allowing the noconstant option in the random effects equation as does the corresponding user's manual entry (Page 593), although the latter doesn't contain a worked example that exercises that option.

I'd rather not trouble Technical Support with this if someone can readily spot an error.