On Jul 5, 2012, at 1:23 AM, luigi scarso wrote: On Thu, Jul 5, 2012 at 12:44 AM, Rogers, Michael K > wrote: XML documents should form a tree, so a structure like \startA % \startB % \stopA % \stopB % won't translate to XML. Grouping in TeX follows the same restrictions, and \start... and \stop... behave like \begingroup and \endgroup. The \stop... is supposed to restore the state before the corresponding \start... (at least I assume so -- \endgroup works that way). One cannot stop A in the middle of B and return to the state before \startA without also stopping B. So one should put \stopB before \stopA, not after it. It depends. \starttext \long\def\startA#1\stopA{<\low{A}#1>\low{A}} \long\def\startB#1\stopB{<\low{B}#1>\low{B}} \startA textAA \startB textAB \stopA textBB \stopB \stoptext is ok (not the context way, btw: real code is more complex). The meaning of this can be content of \startA..\stopA = textAA ⋃ textAB content of \startB..\stopB = textAB ⋃ textBB \startA..\stopA ⋂ \startB..\stopB = textAB If we are describing programs, textAB can be the common code between the function A and B. -- luigi Again, I agree with what you write. Somewhere I must have expressed myself poorly and I apologize. It seems like a side issue (my issue with XML), and I did not mean to hijack the thread. Sorry. ________________________________ This e-mail message (including any attachments) is for the sole use of the intended recipient(s) and may contain confidential and privileged information. If the reader of this message is not the intended recipient, you are hereby notified that any dissemination, distribution or copying of this message (including any attachments) is strictly prohibited. If you have received this message in error, please contact the sender by reply e-mail message and destroy all copies of the original message (including attachments).