- string s = "", join = ":"; \
- FOREACH(id, true, s = strcat(s, join, it.registered_id)); \
- s = substring(s, strlen(join), -1); \
+ string s = ""; \
+ FOREACH(id, true, s = strcat(s, ":", it.registered_id)); \
+ s = substring(s, 1, -1); /* remove initial ":" */ \