res->location = merge_text(a->location, b->location);
res->notes = merge_text(a->notes, b->notes);
MERGE_MAX(res, a, b, maxdepth.mm);
res->location = merge_text(a->location, b->location);
res->notes = merge_text(a->notes, b->notes);
MERGE_MAX(res, a, b, maxdepth.mm);