E0SET
#define INIT0(ei) (TAILQ_FIRST(E0SET(ei)))
candidate = find_escape(E0SET(ei), ch);
while ((escape = TAILQ_FIRST(E0SET(ei))) != NULL) {
TAILQ_REMOVE(E0SET(ei), escape, entry);
escape->set = E0SET(ei);
TAILQ_INSERT_TAIL(E0SET(ei), escape, entry);
TAILQ_INIT(E0SET(ei));